Processing meat products responsive to customer orders

[0001] This application is a divisional of Application No. PCT/US01/45146, filed Nov. 28, 2001, which is a continuation-in-part of application Ser. No. 09/724,287, filed Nov. 28, 2000 now abandoned, which is a continuation-in-part of Application No. PCT/US00/29038, filed Oct. 19, 2000, which is a continuation-in-part of application Ser. No. 09/550,399, filed Apr. 14, 2000, now abandoned, which is a continuation-in-part of application Ser. No. 09/392,074, filed Sep. 8, 1999, now abandoned, which is a continuation of application Ser. No. 09/039,150, filed Mar. 13, 1998, now abandoned, which claims the benefit of Provisional Application No. 60/040,556, filed Mar. 13, 1997. application Ser. No. 09/550,399 claims the benefit of Provisional Application Nos. 60/129,595, filed Apr. 15, 1999; 60/141,569, filed Jun. 29, 1999; 60/144,400, filed Jul. 16, 1999; 60/148,227, filed Jul. 27, 1999; 60/149,938, filed Aug. 19, 1999; 60/152,677, filed Sep. 7, 1999; 60/154,068, filed Sep. 14, 1999; 60/160,445, filed Oct. 19, 1999; and 60/175,372, filed Jan. 10, 2000. Application No. PCT/US01/45146 claims the benefit of 60/255,684, filed Dec. 13, 2000; 60/286,688, filed Apr. 26, 2001; 60/291,872, filed May 17, 2001; 60/299,240, filed Jun. 18, 2001; 60/312,176, filed Aug. 13, 2001; 60/314,109, filed Aug. 21, 2001; 60/323,629, filed Sep. 19, 2001; and 60/335,760, filed Oct. 19, 2001.

[0002] The present invention relates to methods and apparatus, and the products made therefrom from processing and packaging under conditions of reduced oxygen for substantially decontaminating and prolonging the shelf life of perishable goods, such as beef. substantially decontaminating and prolonging the shelf life of perishable goods, such as beef.

[0003] A problem in the meat packing industry is the formation of metmyoglobin and growth of aerobic bacteria on finished packages of meat, reducing the shelf life of meat and ending in vast amounts of waste. Metmyoglobin is an oxygenated form of myoglobin, a protein in meat. The problem arises when the meat, in either ground or sliced form, is exposed to air for too long. Deoxymyoglobin is a precursor protein which when oxygenated forms oxymyoglobin in a normal atmosphere of oxygen. Oxymyoglobin is responsible for the bright red color of meat which is desirable. When oxymyoglobin is immersed in a substantially oxygen deficient atmosphere, the process reverses itself and the oxymyoglobin will reduce, yielding oxygen in gas form or dissolved in the surface water of the meat. If the free gas space in the package is very small, such as a chubb package, or even a vacuum package, the relative percentage volume of oxygen can become very high. This can lead to metmyoglobin formation, discoloration and growth of aerobic bacteria in the areas of high oxygen concentration.

[0004] Previous methods of controlled atmosphere or modified atmosphere packaging have sought to eliminate oxygen in packages, however, not realizing the detrimental effect that oxygen trapped in the form of oxymyoglobin can have, once packaged. Bright red meat, full of oxymyoglobin, packaged in low oxygen will inevitably result in the worst looking meat. Attempts to deal with this included using oversized packages with excess amounts of free space in the package. Further, methods of processing beef are beset with other inefficiencies and problems.

[0005] For example, typically all carcasses are chilled prior to further processing, yet the carcasses contain a great deal of bone and other materials that are not used for human consumption and yet the entire carcass is chilled prior to processing. Furthermore, the shape of meat primals made into food items used for human consumption are of irregular and inconvenient profile. Conversely, packaging trays that have been cost effectively and efficiently manufactured, are invariably rectangular and/or square in profile. By adopting procedures disclosed herein, it will be seen that costs of chilling are reduced since, for example, the skeleton can be removed before chilling thereby saving costs of such chilling process. Fresh red meat tissue is typically quite soft and easy to cut immediately after the animal has been slaughtered and prior to the natural, “hardening” effects of rigor mortis has occurred. It can therefore be easier and quicker to cut primal portions from animal carcasses, during the normal animal “disassembly” process prior to rigor mortis and chilling. Those fresh red meat primal items, that are intended for human consumption, can then be shaped by placing into molds of a specifically designed and desired profile prior to rigor mortis and then chilled during the natural rigor mortis process. This device will provide a method to change and adjust the shape of fresh red meat primal items so that, for example, fresh red meat primal items can be readily and automatically processed during the slicing and cutting process as required prior to packaging. Furthermore, profiles of primal meat portions can be fixed so as to be more convenient when slices of fresh red meat primal items are loaded into improved packaging, such that packaging volume can be efficiently utilized, while still maintaining a space efficient, appealing and attractive appearance for the consumer at the point of retail display and/or food service outlet.

[0006] Typical modified atmosphere packages for fresh foods, such as red meats and other perishable foods, have a limited shelf life, and typically include a thermoformed tray or other package composed of EPS/tie/PE (barrier foam trays) plastics material or other suitable substantially gas impermeable material, i.e., tray, overlaid with a single transparent web of plastics material that can be heat sealed to the tray. A typical substantially gas impermeable heat scalable composite web includes a biaxially oriented polyester (PET) layer/tie layer/gas barrier layer (such as PVDC) an adhesive layer/heat sealing layer (such as polyethylene), which in turn is finally adhered by a heat sealer to the tray. The polyethylene layer is a heat sealable layer that is tied to a gas barrier layer such as polyvinylidene chloride which is in turn adhered to polyester. Because of the diverse types of materials that are employed in the foregoing package, it is difficult to reprocess and recycle the post-consumer package. Moreover, the cost associated with post-consumer recycling of multiple layer plastics material renders the process impractical and substantially not economically feasible.

[0007] Commonly used modified atmosphere packages for fresh foods such as red meats and other perishable foods having a limited shelf life typically comprise a tray thermoformed from a sheet of EPS (expanded polystyrene) laminated to a web of substantially gas impermeable web material or other suitable substantially gas impermeable material. A lid, such as a single or composite transparent web of plastics material that can be bonded to the flanges of the tray. Both tray and lid materials are typically substantially gas impermeable heat sealable composite structures and cannot be readily recycled. Lid material typically comprises a laminated structure including several layers such as bi-axially oriented polyester bonded to a gas barrier layer (such as PVDC) which is sandwiched between an adhesive or heat sealing layer (such as polyethylene). Because of the diverse types of materials that are employed in the foregoing package, it is difficult to reprocess and recycle the “post-consumer” package. Moreover, the cost associated with post-consumer recycling of multiple layer plastics material, such as the aforementioned, renders the process impractical and substantially not economically feasible.

[0008] A further limitation of packaging perishable goods such as fresh red meats in hermetically sealed gas barrier packages results from the need to enclose a relatively large volume of gas, within the package. Clearly, consumers have no interest in purchasing these gasses that accompany the red meat. Minimizing the size and bulky appearance of such packaging is desirable. Additionally, a major proportion of red meat production occurs at locations that are located at a substantial distance from the point of retail sale of red meats to consumers. Most U.S. beef is produced in the central plains around Kansas, Nebraska and Iowa and the major markets are situated on the coastal regions such as New York or California. Costs of shipping these fresh red meat items from the point of production and packaging can be reduced if the packages are reduced in volume. However, reduction in the volume of gases provided within a package can have a deleterious effect on shelf life of the perishable goods and red meat contained therein as explained above.

[0009] The packaging industry has therefore felt the need for simplified individual packaging structures that will provide finished package performance including label requirements for a variety of applications. Additionally, if the packaging can be handled economically both in the pre-consumer handling and in post-consumer recycling, significant economic advantages are available.

[0010] With conventional packaging of meats and other perishable type goods, the shelf life is limited due to bacterial growth within the package. The growth can be inhibited when the package contains carbon dioxide gas, however, carbon dioxide will dissolve in liquids such as water contained within the goods in the package. After time, carbon dioxide can become substantially dissolved in the water, limiting the shelf life. When carbon dioxide dissolves into liquids and water, this can cause the package to collapse inwardly. Collapsing causes the appearance of the package to be unacceptable to consumers and can also cause the package to rupture.

[0011] In order to extend shelf and storage life of the packaged goods several inventions have been disclosed and examples of known packaging for this purpose are given in the following U.S. patents:

[0012]

5,779,832	Kocher	Method and Apparatus for making a peelable film
5,629,060	Garwood	Packaging with Peelable Lid
5,560,182	Garwood	Packaging Method
5,534,282	Garwood	Packing Perishable Goods
5,514,392	Garwood	Packaging for Perishable Goods
5,323,590	Garwood	Method of producing food packaging with
		gas between tensioned film and lid
5,226,531	Garwood	Food Packaging with gas between tensioned
		film and Lid
5,155,974	Garwood	Food Packaging with gas between tensioned
		film and Lid
5,115,624	Garwood	Thermoplastic skin packing means
5,129,512	Garwood	Packaging

[0013] The subject matter of the above patents is hereby incorporated by reference.

[0014] Prior art as described in U.S. Pat. No. 5,779,832 to Kocher, discloses a method of making a multilayer peelable film. Kocher discloses a method of co-extruding two webs of material simultaneously in the form of a multilayer film that can be delaminated into a third web and a second web and then, after treating the second web to improve gas permeability therethrough, re-laminating the third and second webs together. These two re-laminated webs can be sealed to a first web of gas barrier material and thereby produce a package. The first web may have a depression formed therein into which goods such as red meat can be placed before heat sealing the third and second webs to the first web. Typically, goods will not completely fill the depression and space will remain in the depression in addition to the goods. A blend of gases or a single gas such as CO₂ can be provided in the space with the goods and thereby can contact the goods. After storage and prior to retail display at an intended point of sale to consumers, the third web can be peeled from the package allowing atmospheric oxygen to permeate the second web of gas permeable material and to contact the goods. The atmospheric oxygen can then allow generation of a bright red colored substance such as oxymyoglobin thereby providing an appearance attractive to the consumers.

[0015] It has been found that when applying the second and third webs extruded in the manner as disclosed in Kocher to packaging as that disclosed in the inventor's own U.S. Pat. No. 5,534,282, a dull appearance of the second web can result with reduced clarity when compared with other webs of material that are produced in a single web such as plasticized PVC (pPVC). Furthermore, after removal of the third web, from the re-laminated co-extrusion, by peeling, as described in U.S. Pat. No. 5,534,282, distortions and ripples can appear in the second web. This occurs, partly, as a result of inadequate lateral tension provided in the second web when limited by the inherent limitations of co-extruding the second and third webs simultaneously. This can, therefore, severely detract from the visual appearance of the package in the eyes of consumers.

[0016] Conventional modified atmosphere “case ready” retail packaged fresh red meats and other perishable type goods experience limited shelf life because of bacterial growth, such as aerobic and anaerobic bacteria, on the packaged goods; rancidity “off flavors” caused, in part, by oxidizing fats; and discoloration to visible meat surfaces. The growth can be inhibited when goods are treated by exposure to certain agents prior to packaging and then providing certain gases and/or other agents with the goods within the finished and sealed package. However, some gases such as carbon dioxide gas, for example, can quickly dissolve in substances such as oils and water contained in the goods. After time, carbon dioxide can become substantially dissolved in water which may limit shelf life. Furthermore, when oxygen is present and more particularly when a quantity of approximately 5,000 to 30,000 parts per million of oxygen is present in a gas within a package, discoloration due to formation of metmyoglobin on the visible surface of red meat, reduces consumer appeal of the packaged goods. When carbon dioxide dissolves (into another substance) the combined volume of the residual substances is substantially reduced which can cause the package to collapse inwardly. Collapsing causes the appearance of the package to be unacceptable to consumers and can also cause the package to rupture and render it unfit for use. In compensating for such a deleterious event, several existing packaging systems require large volumes of gas to be packaged with the goods. However, when large volumes of gas are provided, the resultant “bulky” condition does not provide for cost efficient shipping and distribution from the location of packaging to the point of retail sale of the packaged goods.

[0017] Conventional packages for red meat are produced in one or more sizes. When packaging red meats or other perishable goods, the package must conform to the goods. Therefore, if a red meat portion is too large for one size of a package, the next larger size must be used. Oftentimes, this will lead to an overly large sized package introducing inefficiency into the process because of the wasted space. In order to maximize efficient use of the internal space available in a typical road, rail or sea, refrigerated shipping container or trailer, it is important to increase the density and unit weight per unit volume of the packaged perishable goods. The maximized efficient use of the space in the shipping containers can be achieved by adjusting the shape of the inconveniently shaped animal fresh red meat primal portions such that slices of the fresh red meat primal portions will fit and substantially fill the available space within trays of the improved packaging.

[0018] High oxygen case ready packages are inefficient, in large part, due to the inherent need to include a quantity/volume of gas that is equal to, or greater than the volume of the package meat contents. For example, a high oxygen package comprising a barrier foam tray and clear barrier film lid, hermetically sealed to flanges of the barrier foam tray and with a 2 lb. quantity of meat sealed therein will require approximately 1 liter of gas to be enclosed and sealed within the package to ensure that an approximate 10 day shelf life extension can be provided. Said gas (referred to as modified atmosphere) will typically comprise 80% Oxygen and 20% Carbon Dioxide but other combinations that may include relatively small quantities (say <10%) of residual atmospheric nitrogen are also typical. The relatively high level of CO₂ (when compared to ambient atmosphere) is provided to inhibit bacterial growth, and with good storage temperature control, a shelf life for ground, fresh meat can be extended to over 10 days from packaging. The bacterial controlling effect is a consequence, in part, of a characteristic of bacteria entering a “lag phase” when the environment in which it is placed, significantly changes. Eventually, the bacteria will adapt to the atmosphere that is present and commence normal, reproduction and extended infection. The shelf life extension will vary according to several factors including, for example, the following storage temperature, i.e., the less variation from a minimum temperature of approximately 29.5° F. is optimum, (while ensuring that freezing of the meat, which occurs at about 26-27° F., does not occur); the condition and age of the meat at packaging, the conditions at the point of packaging such as hygiene, temperature etc., muscle type and age of animal from which the meat was harvested. Nevertheless, a shelf life extension of 10 days is readily reproducible when conditions are maintained as required. After a relatively short period of time, the CO₂ provided within the package will dissolve into the water and oils contained in the meat and the oxygen is present to ensure that a consumer appealing/acceptable “bloom” or “redness” is maintained. The “bloom” is caused by the natural color of oxymyoglobin and oxyhemoglobin that is present in freshly cut meat but when oxygen is present, after approximately 9 to 10 days discoloration such as browning due to increased levels of surface metmyoglobin will occur, rendering the product unsalable or requiring a reduction in price to sell to a consumer. Furthermore, the excessive volume of the finished packages, results in excessive packaging material and shipping costs and display case space at retail outlets and also excessive costs incurred for disposal of additional cardboard, etc., at the supermarket outlets.

[0019] Effective packaging materials for existing, extended shelf life, retail packaged, case ready perishable goods are often relatively expensive and the associated packaging processes are typically labor intensive. The use of EPS and FP can provide desirable low cost packaging materials but the inherent cell structure of these materials can retain residual oxygen (from air) within the cell structure, even during and after exposure to very low levels of air pressure (vacuum). When EPS and FP materials are used in low residual oxygen modified atmosphere packaging, such as described in U.S. patent application Ser. No. 09/039,150, residual oxygen can diffuse and exchange from the cell structure, and become present as a free gas within the master container thereby elevating the level of oxygen present therein to a potentially undesirable level. As described in the subject matter of U.S. patent applications in the name of the present inventor, apparatus for minimizing the level of residual oxygen retained in the cell structure and master containers are disclosed. However, such a process of gas exchange is problematic and difficult to reliably maintain. Therefore, packaging fabricated from solid plastics sheet, may be more efficiently employed in this present application.

[0020] Conventional “master container” or “master package” modified atmosphere packaging (MAP) systems include loading perishable goods into trays and then a plurality of loaded trays are subsequently placed into a larger “master container” which may be manufactured from a suitable gas barrier material. The “master container” is typically evacuated of air and then filled with a gas blend that may include a mixture of any desirable gases which may include, for example, 40% carbon dioxide and 60% nitrogen for a low oxygen MAP system. The master container is then sealed with loaded trays to provide an airtight, sealed master container, containing loaded trays and a gas blend with a residual quantity of atmospheric oxygen. Most desirably, for low oxygen MAP systems, the residual quantity of atmospheric oxygen will not exceed an amount of 100 to 300 PPM (parts per million) with the balance of the gas blend including nitrogen and carbon dioxide and/or other inert or oxygen free gases. Low cost packaging materials include foamed polystyrene (EPS trays), however, the choice of material for tray manufacture must exclude materials (unless treated in a manner that will substantially remove atmospheric oxygen from the cell structure), such as expanded (foamed) polystyrene (EPS), that have a capacity to “retain” air, even after exposure to a high vacuum as may occur in packaging processes. Therefore, in order to maintain the residual quantity of atmospheric oxygen at not more than 100 PPM, untreated expanded (foamed) polystyrene (EPS) or FP trays cannot be easily and efficiently used. By way of explanation, EPS trays are typically thermoformed from extruded EPS sheets. A typical method of producing an EPS sheet is to “foam” the melted (liquid) polystyrene by injection of a foaming agent, such as nitrogen, carbon dioxide or pentane, into liquid polystyrene thereby causing it to foam (become frothy, with bubbles and/or tiny gas filled cells within the foam) and then extrude the foam through a slot in a flat or annular die. The extruded EPS can then cool and solidify into a sheet that can be slit and wound onto a roll prior to further processing. Immediately after extrusion of the EPS sheet, cells retained within the foam are filled with nitrogen or other gas (foaming agent) used in the foaming process. However, such a foaming agent gas, if not retained by other means in the cell structure, can quickly exchange with the ambient air during storage and the cells can become filled with air. When placed within a vacuum chamber and exposed to a high level of vacuum, as is normal in a “master container “packaging process for low oxygen MAP systems, cells can retain a quantity of air, even during and subsequent to evacuation (unless the exposure to vacuum is significantly extended to the extent required). The retained quantity of air in the cells, can subsequently exchange with gas within the sealed “master container” which can, thereby, elevate the residual oxygen content of the “free” gas contained within the “master container” above a desirable level.

[0021] A fundamental need that resulted in the development of thermoformed EPS trays initially arose in the modem supermarket. Fresh meats and poultry were processed and retail packaged at the supermarket immediately prior to retail display and sale. EPS foam trays were developed to meet these supermarket requirements, and have provided a functional and low cost retail package, when “over wrapped” with, a low cost web of plastic material such as plasticized PVC. However, with case ready MAP systems, such EPS trays are now required to be shipped in trucks and other means of transport from the point of packaging, which may be located many hundreds of miles from the point of sale. Abuse and damage can occur to the packaging during this shipping. In an effort to protect against damage, rigid and heavy weight cartons with sheets, cushions' and/or columns, made from suitable materials such as chipboard are manufactured and assembled with EPS trays and goods contained therein. Such protective packaging is expensive, bulky and results in excessive shipping costs. Furthermore, excessive packaging, as required for the sole purpose of protection during shipping, must be discarded at the supermarket thereby creating excessive waste disposal problems with the attendant costs to the environment. It would therefore be desirable to produce rigid packages and containers that can withstand the abuse of long transportation routes.

[0022] Typically meat packing companies slaughter cattle and then process the dressed carcass by chilling and then disassembling the carcass into portions of meat which can then be, in part, delivered to the point of sale to consumers, in vacuum packs. However, approximately 40% of the disassembled meat is processed by coarse grinding and then blended to provide ground meat with a selected with a selected fat and lean content as required by the retailer. The fat and muscle content of the ground meat may be, for example, 20% fat and 80% lean. Typical current processing methods require that the boneless meat be firstly coarse ground then blended, vacuum packaged, delivered to a supermarket or packaging facility close to the consumer where the coarse ground meat is fine ground and then retail packaged immediately prior to retail display. This conventional process inherently results in excessive exposure of the ground meat to ambient atmosphere including oxygen during the grinding and blending process at the point of slaughter. Furthermore, this process requires that relatively large quantities of ground beef are blended together in a single batch. Because it is not possible to disassemble a carcass and provide boneless meat therefrom with a precise and selected ratio of fat to muscle tissue, the typical batch blending process often requires several attempts to produce the desired ratio of fat to lean content. The general industry practice is to deposit selected boneless beef with a fat to lean ratio as close to a desired tolerance as possible. The selected boneless beef may have a fat to lean ratio of 15% fat to 85% lean +/−5%. Typically, a sample of the blended boneless beef is then removed from the blender and then can be tested to determine fat and lean content using, for example, a device known as an Analray testing procedure. After determining the fat and muscle content of the coarse ground meat, additional fat or lean meat is added to the batch blender and the full batch is again blended for a period of time and then a second sample is extracted and tested to determine fat and lean content. If the fat and lean content is as required at this point, the batch of coarse ground meat can be vacuum packaged and stored in refrigerated facilities prior to delivery to the point of retail sale. However if the fat and lean content is not as required, then, additional fat or lean meat can be added to the batch and further mixing is then required. This process is often repeated as many as 5 times or more. Each time the coarse ground meat is blended again it is damaged by the blending process. This damage may include “fat smear” or over heating. Heat is generated during this blending process and “fat smear” occurs when the meat has been exposed to excessive blending. This procedure is expensive in terms of energy, labor and equipment time. Furthermore, damage to the ground meat is undesirable and yet damage typically occurs as a matter of normal process with the currently predominant industry procedures. During the process described above the meat is exposed to ambient air and bacteria such as E. coli 0157:H7 and other dangerous bacteria can be present in the blended ground meats. Excessive blending can cause the bacteria to spread throughout the batch of meat in the blender.

[0023] Ground meat such as ground beef is produced by processing selected portions of boneless meat, including fat and muscle tissues, through a grinding machine. The relative quantities of fat and muscle contained in any batch of the portions of boneless meat is typically arranged to correspond with set industry standards. The batch of boneless meat may include about 93% muscle tissue and therefore the balance of about 7% would be fat. The following TABLE 1 of items 1 to 5, shows the fat and muscle tissue content of some typical industry specifications for boneless meat:

[0024]

TABLE 1
Item	Muscle Tissue	Fat Tissue
1	93%	7%
2	90%	10%
3	75%	25%
4	65%	35%
5	50%	50%

[0025] Although the industry standards are established, it is difficult to produce large quantity of boneless beef to any specification or ratio of fat and muscle. This difficulty can arise as a result of genetic variation in the animals from which the boneless meat is harvested. Consequently, there is often variations that could be as much as +/−2% to 3%, which corresponds to a possible variation of up to 6% and perhaps even more, in the actual fat or muscle content of the boneless meat.

[0026] Typically, consumers can purchase fine ground beef with a fat content that is specified and clearly marked on any retail package. The fat content may be specified to 10%, 25%, or 30% and it is illegal, in several U.S. states, such as California and New York, to sell such retail products to consumers if the fat content is higher than the amount shown on the retail package. Therefore, producing retail packages of ground beef with a fat content of, for example, 25%, may be achieved by grinding a known quantity of Item 2 (listed above) and blending this with a known, measured and corresponding quantity of Item 4 (listed above). The fat content of the resulting ground beef can be measured but it is common for the fat content variation in the initial quantity of the boneless beef items to vary to such an extent that a compensating procedure must be accommodated during production of the product for retail packaging. This compensating procedure can often result in production of ground beef that has a muscle content that is higher than is specified on the retail package. The consumer, however, only pays for the ground beef according to the fat content shown on the retail package. Thus a loss of profit for the ground beef producer can be incurred.

[0027] Typically, a quantity of boneless beef, with a specified muscle and fat content, for example, Item 5, is loaded into a hopper which is connected directly to a primary meat grinder. The portions of meat are progressively carried, by augers and compressed into a tubular line with a perforated grinding plate fitted across. The grinding plate is typically manufactured from suitably hardened steal and the perforations may include drilled and reamed holes of a chosen diameter, which may be about 0.5″ diameter, and which extend completely through the grinding plate. The primary grinder typically produces coarse grinds with the diameter of the meat pieces corresponding with the diameter of the drilled and reamed holes in the grinding plate.

[0028] After primary grinding a quantity of Item 5 may be blended with a selected quantity of coarse ground Item 4. After the blending of Item 5 with Item 4 the resultant mix is processed through a secondary fine grinding machine prior to portioning and retail packaging. The secondary fine grinding machine may be similar to the primary coarse grinding machine except that the grinding plate can be drilled and reamed with holes of less than about 0.25″ diameter.

[0029] Typical fine ground meat for retail packaging and sale to consumers may be produced with fat and muscle content as shown in the following TABLE 2:

[0030]

TABLE 2
Item	Muscle Tissue	Fat Tissue
1F	90%	10%
2F	75%	25%
3F	65%	35%

[0031] The existing grinding, blending and processing equipment, such as that made by the Weiler/Beehive Company, has been demonstrated as effective for grinding meats of various types. However, little has been proposed to improve the quality of the ground meats by, for example, arranging equipment in such a manner so as to substantially prevent contact of the ground meats with air and/or atmospheric oxygen during the grinding and blending processes. The conventional equipment does not allow for continuously and automatically grinding, measuring and blending the ground meats in such a manner so as to continuously produce quantities of ground meats to an exact and predetermined muscle and fat content. In particular, nothing has been proposed in the way of automatically controlling the fat content.

[0032] The present invention provides methods, systems and apparatus to automatically and continuously grind, condition, blend, treat and package the ground meat products with improved accuracy of muscle tissue to fat tissue ratio, so as to minimize losses to the processor. The ground meat can then be packaged in suitable packaging that will enhance the keeping qualities of the products and provide a safer effective method of delivering the goods to consumers.

[0033] Bovine Spongiform Encephalophathy (BSE) is an incurable disease, that can “jump” from cows to humans, and is considered (albeit low) a threat to the US beef industry. It has been, typically, contracted by cattle as a consequence of the animal eating “blood & bone meal” that has been used as a component of the animal's feed where the “blood and Bone” meal has been derived from a cow that has BSE. The practice of feeding “blood & bone” to cattle in their feed is now illegal in the USA and many other countries but there is still a risk of the disease being imported from a country that still allows this practice. Furthermore, a cow can become infected by eating as little as 1 gram of contaminated meal. BSE has been reported in 18 countries and is a threat to the US beef industry. BSE is not believed to be contagious and can only be contracted in humans by consuming of a part of the cow. “Foot and Mouth” or “Hoof and Mouth” is also another threat to the US beef industry and all other cloven foot animals.

[0034] Some one billion lbs. of boneless beef is imported from Australia and New Zealand, into the USA annually. US Federal legislation may someday dictate the requirement to display information on the retail pack to consumers and show the country of origin as well as all other details as, among other things, a guard against illegal imports from banned source countries such as China.

[0035] Global Animal Management (GAM) is a company owned by Schering Plough that has established a system and large computer data-base that is intended to record all information about a beef animal from birth to slaughter. Unfortunately, the value of this information is lost at all US slaughtering plants because they cannot trace the animal through the packing plant disassembly process.

[0036] One broad aspect of the present invention provides for minimizing discoloration of meat due to the formation of metmyoglobin, which occurs as a result from the oxygen released after packaging due to the reduction of oxymyoglobin into oxygen. Therefore, one aspect of the present invention provides methods and apparatus for minimizing the exposure of freshly portioned beef, either freshly sliced or ground, with oxygen. In this manner, freshly ground or sliced beef is packaged with reduced levels of oxymyoglobin present. To this end, a conduit is provided with any suitable gas, devoid of substantial amounts of oxygen. The conduit comprises any and all equipment used in processing and/or packaging the beef. In this manner, meat is packaged in a state that includes relative high amounts of deoxymyoglobin rather than oxymyoglobin. An example of a suitable gas that may be used to practice the invention includes carbon dioxide. The conduit filled with suitable gas is provided from, in some instances, the point of grinding or blending and continues through the point of packaging. However, it is to be realized that any amount of time spent in a suitable gas will result in some benefit to the beef. In this manner, the amount of oxymyoglobin formed on the beef is maintained at a level that does not result in sufficient quantities of oxygen that after packaging would cause the discoloration or formation of oxymyoglobin of the meat to such an extent that the consumer would reject the item.

[0037] A further broad aspect of the invention, concerns improved packaging for food items that are packaged under controlled or modified atmospheres. One such food package, is produced that occupies less volume and is sturdier than conventional packages. Furthermore, trays made in accordance with the invention require less material, yet are rigid to withstand the abuse over long transportation. One such tray material is extruded polypropylene (co-polymer) sheet. Some instances of trays are provided with channeling apertures, however, other trays can be provided without them. Some instances of trays are foamed, including cells with gas that can be exchanged with more suitable gasses. However, other trays are solid, not requiring foam cell gas exchange.

[0038] Further broad aspects of the invention relate to a method of storing and communicating all the information that pertains to a particular animal carcass onto a container which contains the beef harvested from the particular animal. To this end, certain of the trays made according to the invention are identified with unique markings and the information from the animal is then keyed to each tray. In this manner, the information in the form of a readable device can be carried along with the particular container as the container makes its way in the distribution chain. The information can also be read and stored in a memory bank, and made accessible to all who desire to know such information, such as by the Internet. In one instance, particular use of this information is made for setting a price for the goods at the point of retail or for determining its shelf life. In this manner of pricing, the information can be verified in two ways by reading the tag on each container and also by accessing the information via the communication system. A method of tracing a good from a harvested animal includes associating information pertaining to the animal on a carrying means for the animal or any of its divisions. This information could be stored on an RFID tag, an include such information as country of origin, place or originating location of the animal. In this way, a label can be prepared by being able to trace the origin of the packaged good through the disassembly process.

[0039] In one broad aspect, the methods and apparatus of the present invention are directed at saturating or at least dissolving CO₂ into fresh meat prior to packaging. And further still, any exposure of the meat with oxygen is sought to be minimized. Adequate CO₂ can be dissolved in the tissue of the meat and to such a level that the meat can become a source of CO₂ after packaging. This can be achieved by lowering the temperature of the meat to a minimum (about 29.5° F.) and exposing it to relatively high pressure (ambient to 200 psi or more) CO₂ gas. CO₂ gas dissolves more readily at lower temperatures and therefore a part of the method is to expose the meat to high pressure CO₂ at the lowest temperature above freezing and then retail package the meat in a tray, then over wrapped with a highly gas permeable web of material such as pPVC. If an extended shelf life of say not more than 10 days is adequate, then a barrier pouch master container may not be needed, the CO₂ gas “entrained” in the meat tissue prior to packaging will gradually be released immediately after removal from a higher pressure to ambient and as the temperature elevates during delivery to the point of sale and this can be sufficient to inhibit bacterial growth and atmospheric oxygen in unlimited quantities is available to maintain the requisite “bloom”. In this way, shipping, packaging and display costs can be reduced substantially, while providing an extended shelf life which may be sufficient for some industry packers and supermarkets.

[0040] In one broad aspect, the present invention provides methods, systems and apparatus to automatically and continuously process meat products with sanitizing and bacteria count reducing agents that include the measured and controlled quantities of processing aid water. The system can be directly coupled to the aforementioned meat grinding, conditioning, treating and packaging equipment so as to provide a substantially enclosed system thereby providing a safer and effective method of delivering the goods to consumers.

[0041] In one broad aspect of the invention, a conduit is provided that minimizes the contact of freshly ground or sliced beef with oxygen. Processing of the beef, such as grinding, measuring, blending, decontaminating, slicing, cooking, packaging, tray forming, etc., therefore, progresses in a substantially oxygen deficient environment. In this manner, a gas is dissolved in the beef that results in less oxymyoglobin at the time of packaging and consequently, less metmyoglobin formation after packaging.

[0042] A further broad aspect of the invention concerns the production of pet food made in a manner substantially similar to the food processed for human consumption in accordance with the invention. In this instance, however, much of the left over products, such as entrails, can be used to produce pet food, resulting in a substantial benefit and value increase. In one particular aspect, the pet food can be made aseptic, resulting in a moist pet food that does not require refrigeration. Further aspects of the invention are directed to the manner of packaging, and still further aspects are directed at cleansing entrails, such as intestines, to make into the pet food.

[0421] As used herein, terms take the following meaning, unless otherwise indicated.

[0422] The term “case ready” refers to retail packaged fresh meats (that were typically formerly prepared at the supermarket) that have been packaged ready for retail sale from the meat case at a place of production remote from the supermarket.

[0423] The term “conduit” refers to a substantially enclosed space or volume regardless whether it extends to one or more vessels or equipment. A conduit may include the housings and casings of vessels, equipment, devices and any of their interconnecting portions. “Conduit” may be applied to a series of vessels, equipment and connections and/or it can be applied to any portion thereof, referring sometimes only to a single vessel or connection. In some instances, conduits are devoid of substantial amounts of oxygen, unless otherwise indicated.

[0424] The term “high oxygen modified atmosphere” refers to a blend of gases that includes some or all of the naturally occurring atmospheric gases but in proportions that are different to air and including a high level of oxygen which may be greater than 40%. Such an example would be a gas comprising 80% oxygen and 20% carbon dioxide, however in virtually all applications a residual quantity of nitrogen remains in the sealed “high oxygen modified atmosphere” package.

[0425] The term “low oxygen” or “no oxygen” modified atmosphere” refers to a blend of gases that includes some or all of the naturally occurring atmospheric gases (except oxygen) but in proportions that are different from air and include a low (or zero level of oxygen) which may be less than 300-500 parts per million.

[0426] The term “MAP” refers to modified atmosphere packaging.

[0427] The term “CAP” refers to controlled atmosphere packaging.

[0428] The term “Epsilon GMS-40” or “GMS-40” refers to an apparatus that can be used to measure the fat and/or lean content of pumpable ground meats. The GMS-40 is manufactured and supplied by Epsilon Industries, of Austin, Tex. Additional information is available at Web site: www.epsilon-gms.com.

[0429] The term “AVS-ET system” refers to a system that can be used to identify the composition of boneless meats. The system can identify quantities of fat, muscle/lean tissue, contaminants, bone, metal inclusions and other matter that is transferred, in a continuous stream, through a conduit and into and then away from the AVS-ET system. The system operates best when the continuous stream is exclusive of any voids such as pockets of air. The system is manufactured and supplied by Holmes Newman Associates, 4221 Fallsbrae Road, of Fallbrook, Calif. 92028.

[0430] The term “statiflo blending devices” refers to a continuous, static, and enclosed material blending device that can introduce gases, such as CO₂, into the blended material. STATIFLO is a registered trademark of Statiflo International, The Crown Center, Bond Street, Macclesfield, Cheshire SK116QS, UK. Information is available at Web site: [email protected].

[0431] The term “blending devices” refers to a continuous, static, and enclosed material blending device that can be used to continuously blend such perishable goods as ground meats that comprise substantially two components of fat and lean meat and may also be used to introduce gases, such as CO₂, into the blended materials.

[0432] The term “shelf life” refers to the period of time between the date of retail packaging of perishable goods (that are slowly deteriorating) of acceptable quality and a subsequent point in time or date, prior to the perishable goods having deteriorated to an unacceptable condition.

[0433] The term “PP” refers to polypropylene.

[0434] The term “EPS” refers to expanded polystyrene.

[0435] The term “pPVC” refers to plasticized polyvinylchloride.

[0436] The term “PET,” polyester or “APET” refers to amorphous polyethylene terephthalate.

[0437] The term “heat activated adhesives (or coating)” refers to adhesives that become active and capable of bonding substances or webs together when heated to a suitable temperature, when neither said adhesives nor said substances will bond unaided at ambient temperature.

[0438] The term “OTR” refers to oxygen transmission rate.

[0439] The term “perishable goods” or “goods” refers to any perishable foods such as sliced beef, other fresh meats, ground meats, poultry pieces, fish, lamb, and any parts of animals thereof which are not normally fit for human consumption, but which can be fit for animal consumption, etc.

[0440] The term “liquids and oils” refers to water, liquids, blood, purge, liquid animal fats and oils and the like.

[0441] The term “master container” generally refers to a substantially gas impermeable barrier container that can be filled with finished packages (such as retail packages), evacuated of substantially all atmospheric air, and filled with any suitable gas. However, said “master container” may also be gas permeable if so desired.

[0442] The terms “suitable substance”, “suitable gas” or “suitable gases” refer to any gas or blend of gases, provided at any pressure (suitable pressure) such as 45% oxygen and 55% carbon dioxide at ambient pressure or any other blend of gases. Such a gas, blend of gases agent or agents may include one or a combination of the following: oxygen, carbon dioxide, ozone, hydrogen, nitrogen, argon, krypton, neon, helium, xenon, hydrogen peroxide, potassium permanganate, chlorine dioxide, fluorine, bromine, iodine and/or any other suitable substances. A suitable gas may include a blend of carbon dioxide and nitrogen and oxygen with residual atmospheric gases in any relative proportions. Examples are provided, but are not restricted to any of the following:

[0443] A blend of gases including argon, carbon dioxide, nitrogen and a quantity of oxygen that does not exceed 5% and is not less than 5 PPM (parts per million).

[0444] Air that has been filtered to remove substantially all oxygen therefrom.

[0445] Carbon dioxide and nitrogen in any relative proportions.

[0446] Carbon dioxide and oxygen where oxygen does not exceed 5% and is not less than 5 PPM.

[0447] Carbon dioxide and a quantity of oxygen that does not exceed 5% and is not less than 5 PPM (parts per million).

[0448] Nitrogen and a quantity of oxygen that does not exceed 5% and is not less than 5 PPM (parts per million).

[0449] A blend of inert gases and a quantity of oxygen that does not exceed 5% and is not less than 5 PPM (parts per million).

[0450] A blend of pentane and nitrogen in any relative proportions and a quantity of oxygen that does not exceed 5% and is not less than 5 PPM (parts per million).

[0451] A blend of propane and nitrogen in any relative proportions and a quantity of oxygen that does not exceed 5% and is not less than 5 PPM (parts per million).

[0452] A blend of butane and nitrogen in any relative proportions and a quantity of oxygen that does not exceed 5% and is not less than 5 PPM (parts per million).

[0453] A blend of a CFC and nitrogen in any relative proportions and a quantity of oxygen that does not exceed 5% and is not less than 5 PPM (parts per million).

[0454] A blend of an HCFC and nitrogen in any relative proportions and a quantity of oxygen that does not exceed 5% and is not less than 5 PPM (parts per million).

[0455] A blend of methane and nitrogen in any relative proportions and a quantity of oxygen that does not exceed 5% and is not less than 5 PPM (parts per million).

[0456] A blend of hydrogen sulfide and nitrogen in any relative proportions and a quantity of oxygen that does not exceed 5% and is not less than 5 PPM (parts per million).

[0457] A blend of carbon monoxide and nitrogen in any relative proportions and a quantity of oxygen that does not exceed 5% and is not less than 5 PPM (parts per million).

[0458] A blend of sulfur dioxide and nitrogen in any relative proportions and a quantity of oxygen that does not exceed 5% and is not less than 5 PPM (parts per million).

[0459] A gas including about 100% carbon dioxide.

[0460] A substance or agent including one or more of the following: isoascorbic acid, ascorbic acid, citric acid, erythorbic acid, lactic acid, succinic acid or mixtures of salts thereof. Glycerol monolaurate, potassium sorbate, sodium sorbate, sodium iodoacetate, potassium acetate, iodoacetomide, potassium iodoacetate, sodium acetate or mixtures or acidic solutions thereof.

[0461] The term “suitable gas pressure” or “water pressure” refers to any pressure that is suitable for the application and may be controlled within any of the following pressure ranges, or any other suitable pressure:

[0462] Suitable gas pressure:

• • [0463] gas at a pressure of 1 PSI to 14 PSI.
  • [0464] gas at a pressure of up to 13 PSI.
  • [0465] gas at a pressure of 13 PSI to 50 PSI.
  • [0466] gas at a pressure of 50 PSI to 80 PSI.
  • [0467] gas at a pressure of 80 PSI to 120 PSI.
  • [0468] gas at a pressure of 120 PSI to 200 PSI.
  • [0469] gas at a pressure of 200 PSI to 500 PSI.
  • [0470] gas at a pressure above 500 PSI.

[0471] Suitable water pressure:

• • [0472] water at a pressure of 1 PSI to 14 PSI.
  • [0473] water at a pressure of up to 13 PSI.
  • [0474] water at a pressure of 13 PSI to 50 PSI.
  • [0475] water at a pressure of 50 PSI to 80 PSI.
  • [0476] water at a pressure of 80 PSI to 120 PSI.
  • [0477] water at a pressure of 120 PSI to 200 PSI.
  • [0478] water at a pressure of 200 PSI to 500 PSI.
  • [0479] water at a pressure above 500 PSI.

[0480] The term “suitable gas temperature” or “suitable water temperature” refers to any temperature that is suitable for the application and may be controlled within any suitable temperature ranges for any suitable period of time, or at any other suitable temperature. Suitable temperature also includes a temperature range which may be a pasteurizing temperature range such as maintaining a product such as a beef primal within a temperature range of not less than 138.5° F. to 140° F. and for a suitable period of time. The temperature range may be maintained at any suitable range such as between 160° F. to 161.50° F. or any other temperature range whatsoever.

[0481] Bond or Bonding refers to sealing or welding of two or more surfaces together by any suitable means such as with any suitable adhesive, RF welding, ultrasonic welding heat sealing, or any other suitable means.

[0482] Hermetic seal refers to a seal or bonding of two or more surfaces of any suitable material together by any suitable means to provide an enclosed space and wherein said enclosed space is rendered fully enclosed in such a manner that will substantially inhibit the passage or communication of any substance such as gas, air or liquids from within said enclosed space to and with the exterior of said enclosed space.

[0483] Pre-Form refers to a thermoformed or suitably fabricated packaging component that has been arranged with one or more hinged flaps that can be folded or bonded to produce a useful packaging tray or container for goods. Pre-forms may also comprise more than one component that are subsequently assembled together to provide one or more components but where the number of items remaining after assembly are less than the number of components from which the remaining items are produced.

[0484] “Valve” refers to any suitable valve to suit the particular needs of the disclosed application. Valves may be arranged to control the flow of gas, liquid, or solids such as powders and can be selected from manufacturers skilled in the arts of valve manufacturing of any particular valve from any suitable materials.

[0485] “CPU” refers to a central processing unit or any suitable computer processor suitable for the application such as are contained in most personal computers (PC).

[0486] “HHRCD” refers to a hand held remote controlling device such as a PALM PILOT®.

[0487] “Fat” content is a component of meat and may mean the measured fat content of a quantity of boneless meat harvested from any species of slaughtered animal such as beef.

[0488] “Meat” can mean any meat harvested from any species of slaughtered animal wherein the meat comprises several components but generally including water, fat, oils, and protein in relative quantities that are not precisely known at the time of harvesting and must be measured to determine the precise ratio of each component.

[0489] SANOVA is a trade mark of Alcide Corporation of Redmond, Wash.

[0490] Any suitable substance, gas, blend of gases, solution or agent may be substituted, included as an alternative or included with any suitable gas or blend of gases that has been specified for any use or application in this disclosure.

[0491] Before disclosure of the methods and apparatus of the invention for processing and packaging perishable meats, a theory is proposed for the formation of metmyoglobin in packaged red meats with reference to FIG. 1. The present invention, in one aspect, provides solutions to the problem of metmyoglobin formation in beef.

[0492] Fresh meats that have been chilled during an adequate storage period will contain large quantities of purple colored de-oxymyoglobin that is unattractive to typical consumers. When chilled meat is sliced in ambient atmosphere, de-oxymyoglobin comes into contact with atmospheric oxygen. Oxidation, converts the de-oxymyoglobin into oxymyoglobin (referred to as “bloom”) displaying a bright red color that is attractive to consumers. However, if the sliced or ground meat will be stored in a low oxygen gas atmosphere, case ready condition, to extend its storage life prior to retail display, the oxymyoglobin that has formed after slicing and/or grinding (but before subsequent packaging in the low oxygen atmosphere), may transfer oxygen gas into the sealed environment of a master container and/or individual trays. Even though the quantity of oxygen transferred by the de-oxymyoglobin is relatively small, it can lead to the formation of undesirable metmyoglobin on the visible surface of the retail packaged red meat in conventional low oxygen case ready packages.

[0493] Metmyoglobin is brown in color and is unattractive to consumers. It is therefore desirable to prevent and/or minimize the extent of the deleterious formation of metmyoglobin. In one aspect, the methods and apparatus disclosed in the following subject matter details preventative methods. In order to provide a more detailed description of the conditions under which undesirable metmyoglobin may form, the following known laws of physics and natural processes are referenced.

2.1. Normal Conditions for Oxymyoglobin Formation

[0494] After storage under normal commercial refrigerated conditions in carcass or vacuum packed conditions, freshly sliced beef will predictably turn bright red (by oxidation of purple colored deoxymyoglobin to bright red colored oxymyoglobin) with a virtually 100% probability, when exposed to ambient air.

2.2. Optimum Conditions for Metmyoglobin Formation

[0495] It is known that optimum conditions for formation of metmyoglobin, at the surface of sliced, fresh beef muscle exposed to a gas occurs when the free oxygen content of the gas is approximately 5,000 to 30,000 ppm.

2.3. Graham's Law of Gas Diffusion

[0496] The rate of gas diffusion is inversely proportional to the density of the subject gas.

2.4. Relationship Between Density of Gas and Temperature

[0497] The density of a gas (and most matter) is inversely proportional to temperature (i.e., the gas density increases as its temperature is decreased).

2.5. Henry's Law

[0498] At a given temperature, the solubility of a gas in a liquid is directly proportional to the pressure of the gas above the liquid.

2.6 The “Mud Puddle Ring” Effect

[0499] According to the present inventor's observations and independently performed empirical trials, the “effect” can typically occur, immediately following conventionally practiced packaging methods, when one, some or all of the following prevailing conditions are generally approximated:

[0500] 1). The subject sliced beef has been allowed to “bloom” as a result of exposure to ambient atmospheric oxygen immediately prior to packaging.

[0501] 2). The temperature of the sliced beef is lower than the gas and packaging materials surrounding it, immediately after packaging.

[0502] 3). The sliced beef is placed in an “enclosed space” defined by the “retail package” including an EPS foam tray (or other) and a high OTR overwrapping web (the “web”). The “enclosed space” is not completely filled with the subject sliced beef and a remaining space (“the space”) is also contained. “The space” is subsequently filled with a “suitable gas” during evacuation of master container.

[0503] 4). The ratio of beef to gas is low, i.e., the volume of suitable gas” is relatively low and the volume beef is relatively high, in the “enclosed space”.

[0504] 5). The “retail package” is placed into a substantially gas impermeable barrier “master container” which is evacuated (including the “retail package”) of ambient air and then filled with the “suitable gas”. The composition of the “suitable gas” can be carbon dioxide, nitrogen and residual oxygen at approximately 100 to <500 ppm. Thereby, substantially filling “the space” and “other space”. The “other space” is defined by the internal space of the master container but excluding space occupied by “retail packages”.

[0505] 6). The temperature of “suitable gas” is lowest at the lowest point (i.e., near the bottom of the retail package) in “the space”.

[0506] FIG. 1 is intended to be representational and not a depiction of the actual “effect” which is described as follows. Immediately after a conventional manner of packaging, the highly oxygenated condition of myoglobin (oxymyoglobin), which is present at the surface of the beef slices 26 starts to reduce, releasing oxygen gas inside the enclosed space 42. At those sliced beef surface locations shown as 28, that are in direct and intimate contact with the web 32 (such that there is no gas between the beef surface and the web 32), the released oxygen gas passes through the gas permeable web 32, directly and diffuses into the other space 40 inside master container 36 but outside retail package 30. This newly released oxygen gas is therefore immediately separated and essentially excluded from within the retail package. Any further gas contact with the beef surface locations 28 in direct and intimate contact with the web is limited to any gas outside the retail package 30, where the oxygen concentration remains relatively low. However, oxygen gas that is released from beef surface locations that are not in contact with the web enter the space 42 inside the retail package 30 and immediately cause a significant elevation of oxygen concentration in the small free space 34 under the web 32. Even though the web 32 is oxygen permeable the rate of oxygen gas diffusion therethrough is such that it can take an extended period of time for the oxygen content in the gas under the web 32 to equilibrate with the oxygen content of gas outside the retail package 30. Furthermore, the temperature of the oxygen atoms/molecules as they are emitted from the surface of the beef is the same as the temperature of the beef, which is significantly lower than the temperature of the gas in the free space 34 and therefore the density of the released oxygen is relatively high. This condition results in two additional effects. The diffusion rate through the web 32 is lower (Graham's Law) and because the density is higher, these newly emitted oxygen atoms tend to sink toward the lowest point in the retail package 30 and/or remain in contact with the sliced beef surface for a longer period than may otherwise occur. Consequently, the partial pressure of oxygen at the surface of the meat increases and, in accordance with Henry's Law, the level of soluble oxygen gas in the meat surface liquid elevates. The temperature of gas in space 42 is higher at the highest point and lowest at the lowest point. It can be concluded that oxygen gas emitted from the beef surface will remain in contact with the surface of the beef for a more extended period at lower locations and therefore higher concentrations will be present at these lower locations. Conversely, lower concentrations will be present at higher locations. Correspondingly, concentrations of metmyoglobin will form in direct proportion to the concentrations of oxygen. The gas in direct contact with the surface of the beef, a layer of gas that is probably less than about 0.01″ in depth, is theorized to be the active gas that effects the surface of the beef. Under the conditions described above, the oxygen concentration in this layer can become significantly elevated.

[0507] The tendency of the relatively heavier oxygen atoms to move toward the lower levels in the space 42 can cause the oxygen atoms to follow the downwardly disposed surface of the sliced beef and be carried with other gases and liquids that are close to the surface of the sliced beef. This condition can increase the level of oxygen concentration at the surface of the beef and cause the oxygen concentration to increase exponentially toward the lowest point in the space 42. Consequently, the oxygen concentration is highest at the lowest point in the space 42. Correspondingly, higher (and darker) concentrations of metmyoglobin occur at the lowest point in the package and visible but lower concentrations occur at the highest point.

[0508] A mud pool drying in the sun can appear to be surrounded by parallel rings that are typically gray/brown in color. These rings are lightest at the furthermost point from the center of the puddle and typically darkest at the center of the puddle, with a gradual color density change between the two points. The color density of metmyoglobin that is formed under the conditions described above increases gradually from the highest point in the package (where the color is the lightest) to the lowest point in the package (where the color is darkest). Hence, the comparison with a mud pool drying under the sun.

[0509] Eventually, any free oxygen gas released by the reduction of oxymyoglobin, will become either reabsorbed in the form of metmyoglobin or will be diffused and equilibrated with the modified atmosphere contained throughout the master container 36. However, the effective, irreversible, deleterious event of formation of metmyoglobin at the visible surface of the meat will have already occurred and under the prevailing conditions prior to intended retail sale of the meat, will permanently remain visible.

[0510] Subjectively, the above occurs in what can appear to be a confusing manner. Beef that is the best looking and most highly oxygenated (i.e., beef having an attractive red “bloom”) before packaging in the low oxygen atmosphere, will, with an almost certain predictability, emerge as the worst looking beef after removal from the master container. Conversely, the worst looking beef (i.e., beef colored by purple deoxymyoglobin) prior to packaging in the low oxygen atmosphere will, with an almost certain predictability, emerge as the best looking beef after removal from the master container.

[0511] Other issues of multiple species mass transfer with chemical reaction (i.e., a potential cause for the mud puddle ring problem in packaged fresh meat) are described as follows.

[0512] 1. Equilibrium between a gas and a liquid is governed by Henry's law which states that the partial pressure of a gas at equilibrium is equal to the Henry's Law constant multiplied by the concentration of the gas in the liquid phase at equilibrium. The gas is oxygen (O₂) and the liquid is water (H₂O).

[0513] 2. Based on the functional relationship expressed in Henry's law, several factors can influence the state of equilibrium between free O₂ in the package and O₂ absorbed in water.

[0514] A. Partial pressure of free O₂ in the in-package atmosphere.

[0515] B. Temperature because Henry's constant is temperature dependent.

[0516] (The work reported by Zhao and Wells indicates that in-package absolute gas pressure can vary in fresh packaged meat, either increasing or decreasing due to a combination of factors including composition, storage time, temperature, pre and postmortem factors, and others). Because total in-package gas pressure can vary, partial pressure conditions of O₂ can vary causing a migration of O₂ in and out of water solely based on consideration of a single factor A (partial pressure of free O₂ in the in-package atmosphere). With respect to factor B (temperature), it is likely that thermal gradients will develop across a product, from the center to the surface, resulting in slight temperature variations experienced within the package. First, this would have two results. The temperature gradients across a product would aid moisture migration within the product. Second, temperature fluctuation would promote a change in O₂ equilibrium concentration within water. In effect, O₂ could be absorbed into water, the water could then migrate, and subsequently be deposited somewhere else in the product.

[0517] As a result of factors A and B, and the role of chemical conversion, it is likely that some aqueous participation is needed. Given this, the question becomes what relative O₂ concentration and reaction time is needed to produce brown metmyoglobin color. Given sufficient time, factors A and B would operate to move O₂, seemingly through the product, to a point to produce the mud puddle ring.

[0518] Because the in-package gas atmosphere in a closely wrapped product package is minimal, the opportunity for bulk convective gas movement by mass transfer within the package is very limited. The enclosed space near the permeable web, product, and tray are particularly prone to the development of a boundary layer that is away from the free mixing of gas molecules within a larger, relatively unconfined headspace. Boundary layer phenomena may include the establishment of a proportionate localized gas concentration compared with the free gas concentration. This situation would aggravate the O₂ conditions outlined above with respect to factors A and B. Therefore, packages with smaller headspace volumes will experience greater aggravation of the above O₂ conditions than packages with large headspace volume.

[0519] Once formed on a slice of fresh red meat, metmyoglobin is essentially a fixed stain, with unappealing appearance and is generally unacceptable to consumers. On the other hand, oxymyoglobin, which imparts an acceptable red bloom color is attractive to consumers and is therefore desirable.

[0520] In one aspect, the present invention provides methods and apparatus for grinding meats such as beef by processing boneless beef through a grinding machine and substantially preventing exposure of the ground meat from contacting ambient air until the ground meat is delivered in any suitable retail package to a point of sale, such as a supermarket. In this way formation of excessive quantities of metmyoglobin and/or any cause of excessive discoloration can be minimized. In one embodiment, the meat can be vacuum packaged after treatment with CO₂ in any one of the methods described herein.

[0521] The pre-treatment of any perishable goods, such as ground beef, as described herein can enhance the keeping qualities of the perishable goods. In one aspect, the goods can be placed into a sealed pressure vessel with a known quantity of suitable gases at any suitable pressure for a suitable period of time and maintained at a suitable temperature. The suitable gas pressure may be selected at a pressure above ambient air pressure. The quantity of the suitable gas can be increased by providing additional controlled quantities into the pressure vessel as desired. The suitable pressure, time and pre-treatment temperature can be precisely controlled and arranged so as to allow the suitable gas to dissolve into any water and oils and/or other substances contained in the goods. The quantity of suitable gas that dissolves into the goods, can therefore be controlled and may be equal to the maximum amount that can dissolve therein at any suitable gas pressure and thereby saturating the goods with the suitable gas in solution. A known amount of gas can be dissolved into the goods at a given gas pressure and pre-treatment temperature. The perishable goods can then be removed from the pressure vessel and packaged in any suitable packaging such as a hermetically sealed vacuum package that may include a gas barrier plastic pouch or container of suitable size. After vacuum packaging the perishable goods into the suitable gas barrier pouch or container, the goods can be stored in ambient atmosphere and maintained within a suitable storage temperature range. The suitable storage temperature range can be maintained at a suitable level above the pre-treatment temperature. A quantity of dissolved gas can emerge from the perishable goods and partially inflate the gas barrier pouch. The size of the gas barrier pouch can be arranged to accommodate the partial inflation without damage to the hermetic sealing of the pouch. The emerged gas then contained within the gas barrier pouch can enhance the keeping qualities of the perishable goods. The emerged gas can subsequently dissolve into the goods again and re-emerge corresponding to any temperature fluctuations that may occur within the suitable storage temperature range. A quantity of free suitable gas can be maintained in gaseous condition with the goods within the packaging and the quantity of free gas can be arranged and controlled at a minimum suitable quantity. However, if the temperature of the goods in the gas barrier pouch is increased as a result of failure of refrigeration or any other type of temperature “abuse” to an unacceptable high level (for example 50° F.) for an unacceptably prolonged period so that the quality of the goods is compromised, additional gas will be released from solution therein and cause further expansion of the gas barrier pouch. The gas barrier pouch can be sized such that it will accommodate a known amount of released gas. The known amount of the released gas can be limited to such an amount that will be released by goods at an acceptable temperature and if the acceptable temperature is exceeded any additional release of gas can cause rupturing of the gas barrier pouch (or any other suitable packaging material). Rupturing of the packaging, therefore, can be used as an indication that goods have endured an unacceptable level of abuse.

[0522] In one aspect, goods may be treated by exposure to an adequate quantity of suitable gases at a suitable temperature and pressure in such a manner so as to allow a specific quantity of suitable gas to dissolve in the goods. The specific quantity of suitable gas can be arranged so as to equal an amount that will saturate the goods with the suitable gas dissolved therein to a suitable level. The goods can then be packaged in any suitable packaging of suitable size which may include an additional quantity of suitable gas contained and hermetically sealed in the suitable packaging with the goods therein. The total volume of the goods with specific quantity of suitable gas dissolved therein plus additional quantity of suitable gas can be arranged so as to completely fill the suitable packaging of suitable size to provide a finished package with goods and the gas sealed therein. Therefore, any change in temperature of the finished package and the goods therein will result in a change in the total volume of the goods plus the additional quantity of suitable gas. The packaging, the goods with the suitable gas dissolved therein, and the additional quantity of suitable gas can be arranged so as to accommodate a known variation (increase or decrease) in the total volume, as desired. The known variation can be used as an indicator of the temperature history of the finished package. For example, the packaging may be provided with a valve indicator that will permanently open or break if the temperature of the finished package with the goods, increases to an unacceptable level and extent so that the volume of gas therein and corresponding pressure thereof increases to an unacceptable level.

[0523] The present invention thus provides methods and apparatus for the treatment of perishable goods, such as beef, within a low oxygen environment.

[0524] In one aspect, the present invention discloses a method of processing and packaging goods in a low oxygen environment, the method including placing goods in an enclosed vessel containing a gas that enhances the keeping of the goods, allowing the gas to contact and dissolve in liquids and oils present in the goods, restricting the formation of oxymyoglobin by substantially displacing ambient air, that may otherwise contact the surface of the goods, with the gas, providing a retail package including two overlapping webs with a space therebetween with at least one of the webs being gas permeable, and transferring the meats from the vessel to a position between the two overlapping webs and into the space without allowing significant formation of oxymyoglobin on surface of the meats. The present invention, thus, provides methods and apparatuses to accomplish these ends.

3.1. Peelable Lids

[0525] In accordance with one aspect of the present invention, trays having peelable lids are disclosed herein. Perishable goods packaged in trays with peelable lids have an extended shelf life. A peelable lid provides a method of delaying the exposure of fresh meat contained within a package to ambient air until a predetermined period, which may occur at the point of sale.

[0526] Referring first to FIGS. 2, 3, and 4, one embodiment of a package 100 made in accordance with the present invention includes a tray 102 into which meat 104 (FIG. 4) or other perishable product is placed. A first web 106 and second web 108 of heat sealable material are then placed over the tray 102 and heat sealed to the upper horizontal flange 110 that extends outwardly from the upper periphery of the tray 102. By draftsman's license, the webs 106 and 108 are shown separated. In actuality, they are in intimate contact throughout their entire length and width. The webs 106 and 108 are also shown to be heat sealed to each other by cross hatching shown in FIG. 4 at location 112 between the two webs, 106 and 108, and between the bottom web 106 and the tray flange 110 at the location 114. In actuality again, there is no substantial thickness at the heat sealed locations, 112 and 114, but in fact, the materials are in intimate contact with each other and/or the flange 110 of the tray 102. Thereby substantially expelling/removing air or gas from therebetween.

[0527] Depending upon the particular design and use of the tray 102, the first web 106 can be composed of a substantially gas impermeable barrier web or a substantially gas permeable web. Similarly, the outer web 108 can either be substantially gas impermeable or permeable. Substantially gas permeable materials include plasticized polyvinyl chloride (pPVC) and polyethylene (PE) or any combination thereof. In one aspect, these can be used in thicknesses from about 0.0004 inches to 0.001 inches. Suitable barrier webs (substantially gas impermeable) are composed of amorphous polyethylene terephthalate (APET) unplasticized polyvinyl chloride (uPVC) and/or a composite material, such as a biaxially oriented polyester/tie/polyvinylidene chloride/tie/polyethylene or any combination thereof. Other suitable materials known to those of ordinary skill can also be employed in accordance with the present invention.

[0528] The trays 102 are made of polyester (APET, amorphous polyethylene terephthalate often referred to as polyester), polyvinyl chloride or other suitable food grade polymers. As used herein, a web is a sheet of material that may have one or a plurality of layers or zones of differing compositions. Also, when the terms “substantially gas permeable” or “substantially gas impermeable” are used, they are intended to reflect the fact that no practical heat sealable material is totally gas permeable or impermeable. Materials disclosed herein as substantially gas impermeable will serve as a barrier layer to the transfer of significant amounts of gas over time. Likewise substantially gas permeable materials will not function as a barrier but will allow ready diffusion of gas therethrough.

[0529] 3.1.1 Method for Producing Peelable Lids

[0530] One aspect of the invention provides a method for producing the peelable lids disclosed above.

[0531] Referring now to FIG. 5, a schematic side elevation of a package sealing arrangement for assembling a package of the type disclosed in FIG. 2 is shown. Trays 102 are loaded with any perishable material 104 and placed in carrier plates on a conveyor (not shown) and conveyed toward a first heat sealing station 116. A roll 118 of heat sealable material is supplied above the conveyor. The sheet of material that will become the inner web 106 from the roll 118 travels downwardly and wraps around a roller 120 and then traverses horizontally in a left-to-right direction along with the trays 102 being conveyed by a conveyor (not shown). A label dispenser 122 positions a label 124 on the upper surface of the inner web 106 of heat sealable material. The outer web 108 of sheet material is then drawn from roll 126 downwardly around another roller 128 and traverses horizontally from left-to-right, where the label 124 is captured between the inner and outer webs 106 and 108, respectively. The two webs and the label are then run through a pair of nip rolls 130 to cause the two webs and the label to come into intimate contact and also substantially removing air from between the webs. The webs of heat sealable material 106 and 108 are then positioned at the heat sealing station 116. Corresponding tray 102 is positioned in the lower portion 132 of the heat sealing chamber. The lower portion 132 of the heat sealing chamber 116 is then raised upwardly toward the upper portion 134 of the heat sealing chamber 116 wherein the webs 106 and 108 are sealed to each other and to the upper surface of the flange/lip portion 110 of the tray 102 around the periphery at the flange. At the same time, a knife 136 incorporated into the sealing chamber 116 trims the excess material neatly around the outer edge of the tray flange 110. The scrap material 138 is then passed around a roller 140 and onto a scrap retrieval roll 142. The tray 102 is then moved onto another conveyor where the finished packages 100 are moved from left to right to a transportation and/or storage station.

[0532] 3.1.2. Apparatus for Forming Peelable Lids

[0533] Referring now to FIG. 6, a schematic side elevation view through a portion of a sealing mechanism 116 is shown. A schematic view is provided so as to disclose an example of a peelable seal mechanism that will facilitate peeling of the outer second web 108 from the package 100 while the first web 106 remains substantially intact and sealed to the tray web 102. The example is provided to show examples of plastics materials that will seal as required when used according to the present invention. Other selected materials may also be used in similar manner without departing from the general ambit of this invention.

[0534] Referring to FIG. 7, in one instance of the tray web 102, first web 102 includes a thermoformed tray produced from a multilayer co-extruded material including a first outer layer 146 of Eastman 9921 about 0.008″ thick and a second inner layer 148, about 0.004″ thick, including a blend of about 50% PETG 6763 and about 50% Eastman 5116 (or Eastman PM14458 or equivalent shown in FIG. 7). First web 106 includes a web of pPVC with a thickness of about 0.0008″. Referring to FIG. 8, outer second web 108 includes a two layer co-extruded web with a first outer layer 150 of Eastman PET 9921 about 0.003″ in thickness and a second inner layer 152, about 0.003″ thick, including a blend of about 16% Eastman PETG 6763 and about 84% Eastman PET 9921.

[0535] Referring again to FIG. 6, a water cooled clamp 154 is shown in position above tray 102, first 106 and second 108 webs and two separate heat seal bars 156 and 158 are arranged adjacent thereto and all are separated by space and are each independently activated, controlled, and moved. Heat seal bar 156 can have a set temperature of about 385° F. and heat seal bar 158 can have a set temperature of about 370° F. For the materials described above, second inner layer 152 of the outer second web 108 will heat seal to the first web 106 when the temperature at the interface of first and second webs reaches about 385° F. and above. First web 106 will heat seal to second inner layer 148 of tray web 102 when the temperature of the interface between the tray and first webs is about 370° F. and above.

[0536] In one aspect, the water cooled clamp 154 is mounted to an independently activated pneumatic driver (not shown), providing downward pressure such that the water cooled clamp 154 can clamp against tray 102, first 106 and second 108 webs so as to hold them firmly against the rubber seal 160 located beneath the tray web flange portions 110 and 162. Heat seal bars 156 and 158 are independently attached to pneumatic drivers (not shown) for applying pressure thereto so as to facilitate a method to seal second 108, first 106 and tray 102 webs together under independently selected pressure. Heat seal bar 156 heat seals the second 108, second 106 and tray webs together at 112 and 114 and heat seal bar 158 heat seals the first web 106 to the tray web 102 at 164 but does not heat seal the interface between the second 108 and first 106 webs. When the package, is assembled and sealed in the foregoing manner, the second web 108 can be peeled from the package without rupturing the first web 106. First web 106 may be perforated so that after seals 112, 114 and 164 have been provided, the first 106 and second 108 webs can be separated to provide a space 166 therebetween.

[0537] Seals at 112, 114, and 164 have been shown as heat seals, however, effective sealing can be achieved with use of ultrasonic devices or alternatively latex rubber adhesives when applied at the interfaces of the webs at 112, 114, and 164, or with any other suitable method of sealing. Such sealing can provide improved economics while still providing an effective peeling mechanism as required and described above.

3.2. Trays

[0538] In another aspect of the present invention, methods, and apparatuses are disclosed that facilitate the evacuation of gases from packages to minimize the formation of metmyoglobin on the surfaces of meats. These features are incorporated into the design of several embodiments of trays herein disclosed.

[0539] To facilitate the elimination and removal of undesirable gases from within trays, one embodiment of a tray formed in accordance with the invention includes a valve. In some instances, trays made according to the present invention provide channeling or directing a fluid from within an interior of a tray to the exterior, including the evacuation and introduction of any gases and liquids. Furthermore, trays formed in accordance with the invention provide numerous other advantages. Without limitation, one advantage that is realized is the capability to be stacked atop one another.

[0540] Conventional thermoformed trays are made in molds which have sides that are generally inclined to facilitate separation between the mold and the tray. Thus, the bottom of the tray is typically smaller than the top of the tray. Consequently, conventional trays are cumbersome to stack when filled, because the smaller area at the bottom cannot be suitably supported by the larger opening at the top. Trays constructed according to the present invention include members, in the form of flaps that provide a suitable resting area for the lower portion of the tray when stacked atop one another.

[0541] 3.2.1. Embodiment

[0542] Referring now to FIG. 9, a portion of a tray embodiment with a valve constructed in accordance with the present invention is shown. In this embodiment, the tray 200 has an upper peripheral flange 202 that extends outwardly from the entire upper periphery of the tray opening. The tray sides extend downwardly to the horizontally disposed bottom. A downwardly extending recess 204 is cut or formed in the tray corners. The edges of the recess 204 communicate with the interior of the tray. At the inner portion of the recess, the recess and the wall of the tray terminate in an opening 206. The opening 206 has its upper edge at the same level as the upper surface of the flange 202. The lower edge of the opening is in communication with the exterior of the tray, allowing liquids and gases to exit the tray, forming a valve. However, if the tray is tipped, undesirable liquids can flow into the recess 204 and back out through the edges of the recess 208. In this manner the undesirable juices/liquids will not easily exit the package through the opening 206.

[0543] 3.2.2. Embodiment

[0544] Another embodiment of a tray with a valve is shown in FIGS. 10-12. The longitudinal edges of the tray 300 each include a flange having an outer 302 and inner 304 flange. The outer flange 302 is coupled to the inner flange 304 of the tray 300 by a hinge member 306. The inner flange 304 is integral with and extends outwardly from the upper edge of the tray 300. A recessed platform 308 is formed across the corner of the tray at opposite diagonal corners of the tray. The bottom of the platform 308 is lowered slightly relative to the level of inner flange 304. The platform 308 in the edge of the tray carries a small depression 310, the bottom of which is perforated. During evacuation and flushing, gases can rapidly enter through the perforation in the depression 310, travel through the recess formed by platform 308 into the interior of the tray and vice versa. Adjacent to the recessed platform 308, the flange includes an outwardly extended flap 312. In the unfolded position shown in FIG. 10, the flap 312 carries a concave dimple 314 (viewed from the top in the unfolded position). The dimple is located relative to the hinge 306 such that when the outer flange 302 is folded over on top of the inner flange 304, the dimple 314 resides approximately directly above and central to the depression 310. When desired, the dimple 310 can be depressed from the upper side so as to reverse its concavity. When the concavity is reversed, it extends downwardly into depression 310, closes off the perforation in the cavity, and thus seals the container.

[0545] Referring now to FIG. 11, the tray 300 has a recessed bottom 316 so as to form peripheral legs 318 upon which the tray 300 rests. A first and second web 320 and 322, respectively, of heat sealable material overlay the upper portion of the tray 300 and are heat sealed to the upper surface of the inner flange 304. However, it is apparent to one of ordinary skill that a single web, such as the first web 320 may be incorporated alone by deleting the second web 322. A label 324 or other indicia bearing material can be sandwiched between the heat sealable webs 320 and 322. The method for incorporating a label between a first and second web has been described above.

[0546] The label 324 sandwiched between heat sealable webs 320 and 322 is optional and can cover the entire upper surface of the tray 300. Alternatively, the label 324 can cover only a portion of the product contained in the tray 300. The label 324 can carry graphics that, for example, show the contents in a fully prepared and cooked condition to suggest to the consumer how the product will look when cooked, yet allowing the consumer to see at least a portion of the fresh product in the tray. For example, if the tray contained fresh beef patties, the label could cover half of the exposed upper surface. The label may be arranged with a straight cut or opening running the full length of the package. Alternatively, the label could be positioned on one side of a diagonal through the package, while the portion of the package on the opposite side of the diagonal would be open for viewing the fresh, packaged product.

[0547] Referring again to FIG. 10, the remainder of the longitudinal extent of the outer flange 302 includes lateral reinforcing ribs 326 that extend upwardly from the flanges 302 when folded over the top of flange 304. Referring now to FIG. 12, a first 330 and second 332 tray are stacked in a manner according to the invention. The reinforcing ribs 326 of the bottom tray 332 have a recess 328 that receives the legs 318 of a substantially similar tray 330 stacked on top of tray 332. The recesses inhibit lateral movement of one tray relative to another. Thus, these containers are stackable for use, for example, in a master container holding a plurality of similarly configured trays.

[0548] 3.2.3. Embodiment

[0549] Referring now to FIGS. 13-16, another embodiment of a evacuable and stackable tray 400 constructed in accordance with the present invention is illustrated. The tray 400 is generally rectangularly shaped. The tray 400 includes first and second sidewalls 402 and first and second end walls 404. Walls 402 and 404 are generally upright and slope inwardly from their upper portion toward the tray bottom 406 to facilitate separation from a mold. The bottom 406 has a raised central portion 408 that slopes downwardly toward the bottom of each end wall 404. The upper end of the sidewalls 402 and end walls 404 terminate in an outwardly extending horizontal flange 410 that extends completely around the tray 400. Walls of tray 400 may have reinforcing ribs running vertically. Furthermore, ribs may run horizontally on the bottom 406 of the tray 400. The raised center portion 408 creates a cavity 412 (see FIG. 14) underneath the bottom 406 of the tray 400. When the trays are filled and stacked, if the contents extend above the flange 410, the cavity 412 will accommodate the raised contents without compression of the contents in a stacked arrangement.

[0550] Referring to FIG. 13, a horizontal platform 414 is formed in diagonally opposed corners of the tray 400. The platform 414 is positioned at an elevation slightly below that of flange 410. A wall segment 416 extends downwardly from the inner edge 418 of the platform 414 and has edges that join with the sidewall 402 and end wall 404. The platform 414 and the wall 416 form a concave recess 430 on the outside of the tray 400. An aperture 420 is formed in the center portion of platform 414 and allows gas communication between the inside of the tray and the outside of the tray via the recess 430 when a web covering the top of the tray 400 is sealed to flange 410.

[0551] Referring still to FIG. 13, the tray 400 also has movable flaps 422 that are hinged via a hinge 424 to the outer edges of the portions of horizontal flanges 410 that extend outwardly from the end walls 404. The flange 422 when open carries a hemispherical shaped dimple 426. The center of the dimple 426 is on a line perpendicular to the hinge 424; this line also runs through the center of aperture 420. The centers of the aperture 420 and the dimple 426 are equidistantly spaced from the hinges 424. Thus, as shown in FIG. 16, when the movable flap 422 is folded over the

[0552] Referring now to FIG. 14, an exploded view of the construction of a finished package is illustrated. Tray 400 is suitably sized to accept a perishable good 436, such as meat within the cavity of tray 400. Product 436 is suitably shaped to the tray 400 dimensions, and a web 434 can be applied and sealed to tray at flange 410 surrounding the tray cavity. Optionally, a label 432 can be applied to the exterior of the web 434 to produce a package as illustrated by FIGS. 14 and 15. FIG. 15 illustrates a tray 400 having flaps 422 in the open position, meaning that flaps 422 are not folded over to lie adjacent to the sealed web 434. FIG. 16 illustrates the intended motion of flaps 422 about the hinge 424 to match dimples 426 with apertures 420.

[0553] Referring now to FIG. 17, when a web 434 of material is heat-sealed over the top of the tray 400, the interior of the tray 400 remains open to the atmosphere through the space between platform 414 and web 434 through aperture 420. As will be better understood below, it is many times desirable to close the aperture 420. This is done by pressing downwardly on the exterior of the dimple 426 forcing it to reverse itself as shown in FIG. 18 and extend downwardly to fill the aperture 420, thus closing it and sealing the inside of the tray 400 from the external atmosphere.

[0554] Referring again to FIG. 14, in one aspect of the present invention, the tray package can be used to store and transport red meat 436, for example, ground beef. In accordance with the present invention, the ground beef 436 may be ground in a conventional grinder. The grinder may be modified so that preconditioned carbon dioxide at a predetermined temperature is injected into the grinder head for two purposes. The first is to cool the grinder head; the second is to allow the carbon dioxide to mix with the ground beef 436 and become dissolved in the liquid therein. The dissolved carbon dioxide will aid in preservation of the ground beef during the storage period.

[0555] A web 434 of substantially gas permeable material is then placed over the tray 400 and beat sealed to the flange 410 in a manner as shown in FIG. 15. The web is taut over the top of the red meat to prevent its movement about the tray during handling. A label 432 may be applied to the upper surface of the web 434 if desired. Alternatively, a dual web can be employed as shown in FIGS. 2, 3 and 4 and a label sandwiched therebetween. Thereafter, the flaps or movable flanges 422 are folded over the top of flange 410 so that the dimples 426 reside over the apertures 420. However, it may be appreciated that any of the aforementioned trays with valves can be used with a dual web. The flaps 422 are then heat sealed along their outer edges to the flanges 410 at a second heat sealing station to form a completed package as shown in FIG. 16.

[0556] 3.2.4. Embodiment

[0557] Referring now to FIGS. 19 and 20, one embodiment of a stackable tray with tray valve constructed according to the present invention is shown. It is apparent that FIGS. 19 and 20 show only a portion of the tray including the flap and valve, and the remainder of tray can be constructed in accordance with any of the embodiments herein described. In this embodiment of a tray valve, a web 500 of substantially gas permeable material is heat sealed at seal 502 to the top of the peripheral flange 504 of a tray 506. A frustoconical tube 508 extends upwardly from ledge 510 and terminates in an opening 512 that is slightly above the level of the peripheral flange 504. After heat sealing web 500 to the peripheral flange 504, the web 500 overlying the opening 512 contacts the upper edge of the frustoconical member thus forming an effective valve to close the interior of the tray 506 from the atmosphere.

[0558] A flap 518 is attached to the ledge 510 at hinge 516. FIGS. 19 and 20 show the flap folded over so that the flap covers the opening 512. At the location adjacent to the opening 512, the flap includes a dome 514 that extends away from the opening 512. Therefore, the web 500 is in intimate contact with the upper edge of the opening 512, but the flap is not.

[0559] FIG. 20 shows the intended operation of the valve. During evacuation of the master container, the portion of the web 500 over the frustoconical member 508 will elastically extend away from the aperture until the gas inside the package is completely withdrawn, allowing full evacuation of the individual container (or retail package). This occurs because the air/gas pressure inside the retail package is greater than the air gas pressure outside the retail package during evacuation. When gas flushing (described in detail below) occurs, which immediately follows evacuation, the web at the opening 512 will again be elastically extended and lifted off the rim of the frustoconical member 508. This again occurs because a partial vacuum remains in the recess of the dome 514 overlying the frustoconical member. Moreover, during gas flushing, at least the initial pressure in the container is less than that on the outside thus allowing gas pressure on the outside to distend the web 500 away from the opening 512. After equilibration, the tension of the web 500 over the rim of the frustoconical member 508 remains so as to effectively close it and prevent ingress of undesirable material into and/or egress of juice or matter from the container 506.

[0560] 3.2.5. Embodiment

[0561] Referring now to FIGS. 21-23, another alternative arrangement for a valve structure similar in operation to that shown in FIGS. 19 and 20 includes a tube section 600 that extends upwardly from the upper surface of ledge 602. The tube section 600 is connected to the ledge 602 by a concentric bellows structure 604 that allows the tube section 600 to move upwardly and downwardly relative to the ledge. In practice, the upper lip of the tube section 600 (which forms an opening into the tray from the outside) is in contact with the web 608. A dimple 610 resides over the upper edge of the tube section 600. During evacuation and gas flushing, the web 608 will distend away from the lip 606 as shown in FIG. 22 of the tube section 600 in the same manner as described in conjunction with FIGS. 19 and 20. However, the tube section 600 may be more permanently closed by depression and reversal of the dimple 610 as shown in FIG. 23. Full reversal of the dimple 610 would push the tube section 600 downwardly against the resistance of the bellows structure 604, forming a very tight closure between the upper lip 606 of the tube section 600 and the bottom surface of the reversed dimple 610.

[0562] Trays constructed in accordance with the present invention provide a way of evacuating the interiors of trays and in some instances can provide a closable mechanism. In addition, trays constructed according to the present invention provide for ledges which allow the trays to be stacked in a convenient fashion in master bag or master containers as will be described in further detail below. Further, valves according to the present invention may be one way only valves.

[0563] 3.2.6. Embodiment

[0564] In one aspect of the invention, trays can be provided with extended flaps that can be folded adjacent to the tray sidewalls, thus providing a double wall construction with an interior space between the inner and outer tray walls. While, reference is made to embodiments that have flaps that can be folded over the exterior wall of a tray, it can be appreciated that the flap and tray, can be constructed wherein the flap is folded in the opposite direction and over the interior of the wall of a tray. A double wall construction provides added rigidity and a means for stacking the trays atop one another. Furthermore, trays with extended flaps made in accordance with the invention include channels and apertures and are capable of being evacuated within a master container. Trays with flaps and trays with channels that are constructed according to the present invention provide sturdier stackable trays that are able to be evacuated of air and flushed with inert gases and additionally provide channels and spaces to retain any liquids exuded from the purchased goods.

[0565] Any suitable substances that enhance the keeping qualities of goods can be provided into the spaces between the flaps and the tray walls. Water, liquid and purge absorbing substances can be provided in those spaces which may be arranged so as to be non absorbing prior to exposure to and capable of absorbing liquids only after exposure to microwaves or a magnetic field.

[0566] Referring now to FIG. 24, a packaging tray 700 with flaps constructed according to the present invention is shown. The tray 700 including flaps 702, 708, 710 and 712 can be thermoformed from suitable materials such as polystyrene, polyester and polypropylene in a solid or foamed sheet. In one embodiment, the tray 700 is suitably thermoformed from an expanded polystyrene sheet of suitable thickness no less than about 0.1 mil and sometimes no less than 1 mil. In some instances, the tray thickness can be adjusted for better utilization of materials, meaning finding the suitable rigidity for the least amount of material used. Tray 700 includes a base with perforations 704. Four upwardly extending sides from the tray base terminate at a common flange 706. Each flap 702, 708, 710 and 712 is attached to flange 706 at the external edge of flange 706 by way of hinges 714. Flap 702 is provided with a profile that mirror images flap 710, and flap 708 is provided with a profile that mirror images flap 712. The flaps are attached to the outer edge of flange 706 at hinges as shown, such that flaps will fold downwardly and intimately contact the outer surfaces of the tray walls. The cross-sectional profile of flaps 702, 708, 710 and 712 are similar, flap 702 and flap 710 being of substantially similar dimensions, and flap 708 and flap 712 being of substantially similar dimensions. Flaps may be formed to include a rim 716 that follows a continuous path around the perimeter of each flap. Flaps include a profile that includes a flap base 718, a flap flange wall 720 and external flap vertical walls 722. Buttresses 724 are formed into the flap profile and connect the flap flange wall 720 to flap base 718. Horizontally disposed ridges 26 and 728 provide horizontal channels that connect buttresses 724 with continuous communication to openings at each end of flaps in flap vertical walls 722. Apertures 730 are provided between the ridges. Apertures 730 thereby provide communication through flaps at locations between the buttresses. Apertures 732 are provided in the upwardly extending walls of tray at points adjacent to the buttresses 724 such that when the flaps are folded into a vertically disposed position relative to the tray 700, apertures 732 provide direct communication through the tray walls with the buttress recesses 734.

[0567] Referring now to FIG. 25, a three dimensional sketch of the tray 700 with flaps folded downwardly, is shown. When the flaps are folded to a downward position, the flap flange wall 720 is in contact with the underside of flange 706. In this position, the flaps are located in close proximity and in contact with the upwardly extending tray sides. Flap base 718 is substantially horizontally disposed relative to the tray 700 and provides an extension to the base of the tray such that when a tray 700 with flaps folded as shown in FIG. 20 is placed directly above a similar tray, the flap base is adjacent to and resting on flange 706 of an underlying tray. It should be noted that while the tray 700 shown in FIG. 24 includes a tray with four flaps, any number of flaps from one to four may be provided according to preferences and any specific requirements of a particular application.

[0568] Referring now to FIG. 26, tray base 740 is shown with perforations 704 therein. Perforations 704 may extend directly through tray base or partially therethrough from either side. Perforations 704 can provide absorption of liquids that may accumulate adjacent thereto, by the open cell structure of the tray base material, such as when the tray has been thermoformed from expanded polystyrene sheet which is, at least in part, of open cell structure.

[0569] A space 750 is shown which can be provided if desired. Space 750 can be provided after a tray with flaps is inserted into a pre-formed shrink bag that is then exposed to elevated temperature that can cause the shrink bag to shrink around the tray with flaps. Alternatively, the profile of the tray with flaps can be arranged such that space 750 is substantially minimized when the tray base 740 is in direct and intimate contact with the shrink bag. Shrink bags may be printed as required with information of interest to any person interested in purchasing the finished package. Such shrink bags are manufactured for example by Robbie Manufacturing Inc., and are well known by the name PromoBag™. Shrink bags can be printed and fabricated from a clear, biaxially-oriented, heat shrinkable, anti-fog, polyolefin film material manufactured by E. I. Dupont De Nemours and known as Clysar AFG anti-fog shrink film. Clysar is a registered trade mark of Dupont, details of which can be obtained from Dupont or on the internet at www.clysar.com.

[0570] Referring now to FIG. 27, a finished package is shown. The finished package includes a cover 760 which may be a shrink bag as described above or any other suitable packaging material. The finished package 762 may contain perishable goods such as fresh red meats or fresh ground meats.

[0571] Referring now to FIG. 26, apertures 752 can be provided at optimized locations and/or as shown, in the outer cover shrink material 760 of the finished package 762. Apertures 752, may be provided in the bag or web of shrink material 754 before or after package assembly, thereby providing direct communication from external atmosphere from apertures 752 through space 758, apertures 730, channels 726, 728, buttress recess 734 and apertures 732, and into the tray cavity 770.

[0572] Referring again to FIGS. 26 and 27, it can be seen that by manufacturing trays having one or more of the features herein described, any liquids that may accumulate within the tray cavity 770, such as blood, will be substantially restricted from escaping through apertures 752 shown in FIGS. 33 and 34. This restriction is provided by the arrangement of flaps, channels, apertures, etc., therein, and the location of the apertures. Furthermore, perforations 704 provide for retention of the liquids within the package.

[0573] 3.2.7. Embodiment

[0574] An alternate embodiment of a tray with flaps constructed according to the present invention is shown in FIGS. 28-29.

[0575] Referring now to FIG. 28, a cross-sectional view of finished package 814 is shown. Finished package 814 includes a packaging tray 856 with perishable goods located in the tray cavity and an outer cover 816. The outer cover 816 includes an envelope of material that completely covers and encloses the packaging tray 856 and the perishable goods and is heat sealed to provide a sealed package. The outer cover 816 may be manufactured from a shrink material such as Clysar, manufactured by DuPont, and can be printed such that all surfaces are rendered opaque leaving a transparent window 822 on the upper surface only, as shown in FIG. 29 of the finished package 814. In one embodiment, Clysar outer cover shrink material is then heat shrunk such that the outer cover shrinks, holding the flaps against the tray walls. Apertures 818 are provided on the four vertical faces of the finished package when the base 820 of tray is horizontally disposed.

[0576] The tray of FIG. 28 includes four flaps similar to the flaps of the tray of FIG. 24, with modifications as described herein. In one aspect of the tray 856, the tray base 820 is substantially flush with the flap ends 841. To this end, the tray walls 817 are substantially planar, but slightly outwardly biased. The lower portion of walls 817 include a recess 819, wherein a corresponding portion of the tray flap 821 mates with the wall, providing a substantially sturdy construction. Recess 819 may be filled with any suitable adhesive to bond flap 821 with the tray 856. Flaps 821 like flaps 702, 708, 710 and 712 of FIG. 24 include a flap end wall that can bond to the underside of the flange 823. Continuing downward, the profile of the flap is to lie adjacent to the tray wall 817, followed by an outwardly protruding first peak or ridge 825 that at one point can make contact with the outer cover 816. Continuing downward from the first peak, the flap profile returns to lie adjacent to the tray wall 817 for a second portion, and then extends at a less obtuse angle that forms a second peak or ridge 827. The flap base 841 is then constructed to lie substantially flush with the tray base 820, and includes a short downward leg 842 that fits within recess 819. Flaps 821 may include a plurality of apertures or channels creating spaces between the inner wall 817 and flap 821 that aid in the channeling and/or retention of fluids, such as any desired gases or juices from the product. Furthermore, any suitable substances for enhancing the keeping qualities of goods can be provided into the spaces between the flaps and the tray walls. Water, liquid and purge absorbing substances can be provided in those spaces that may be arranged so as to be non-absorbing prior to exposure to and capable of absorbing liquids only after exposure to microwaves or a magnetic field.

[0577] Referring now to FIG. 30, a detailed section of an alternate embodiment of packaging tray 856 with base 820, tray wall 817 and flange 823 attached to flap 821 at a hinge 832, is shown. The relative position of flap 821 and the section of tray is in the “open position”. Flap 821 is attached at hinge 832 to flange 823, however flap 821 is not folded downwardly.

[0578] FIGS. 30-31 show an embodiment wherein the tray walls are perforated in sections shown as incision section 826 and incision section 828, shown in FIG. 30. Perforations of the incision sections 826 and 828 may be in the form of small holes or incisions that extend fully through the tray walls, but may be provided only within the limits of the regions shown as incision sections 826 and 828.

[0579] Referring now to the flap 821 of FIG. 30, a cross-section is shown including a first and second raised peaks 827 and 825, respectively, and a flat area shown as face 838 and face 840; also shown are a leg 842; and gussets 844, with connecting sections therebetween. Packaging tray 856 includes a base 820, flange rim 823 with tray wall connecting base of tray 820 to the flange 823. Tray wall 817 includes recess 819 at a lower portion of the tray wall 817 in proximity to the base 820, a first incision section 826, recess 819 and a second incision section 828. FIG. 31 shows a view of flap 821 from the direction of arrow 880. Flap 821 includes a perimeter 830 including hinge 832 connecting flap 821 to the tray flange 823. Face 838 and end flanges 850 are connected together to provide the continuous flat perimeter. Referring now to FIG. 30, a depressed area 852 may be provided in the flap section between peak 827 and ridge 825 but does not perforate the section. Apertures 854 are provided in face 840 to provide direct communication therethrough.

[0580] Referring now to FIG. 32, an enlarged view of a tray portion is shown. Flap 821 and the tray wall 817 are in adjacent contact and leg 842 and recess 819 are engaged. Faces 838 and 840 as shown in FIG. 32, are in direct and intimate contact with the tray wall 817. Face 840 may be located in recess 848, thereby closing apertures 854 when in this position. Spaces 860 and 858 are directly adjacent to first and second incision sections 826 and 828, respectively. Shrink film 816 holds flap 821 firmly and tightly against the tray wall 817 providing sealed contents within the finished package. The package may be colorized to prevent translucency. An adhesive such as a cold seal latex is provided between the continuous perimeter 830 of the flap as shown in FIG. 31 and the tray wall 817. The tray wall 817 is inwardly flexible such that when a vacuum is provided within the tray cavity, the recess 848 and face 840 will separate to provide direct communication from within the tray cavity via perforations or incisions at first and second incision sections 826 and 828 through apertures 854, and through apertures 818 in outer cover shrink film 816.

[0581] As with the other tray embodiments disclosed herein, a plurality of finished packages 814 (see FIGS. 28 and 29) of this embodiment can, as well, be stacked and placed inside a gas barrier master container inside a vacuum chamber. Substantially all the air may be evacuated from within the gas barrier container and from inside the finished packages. Air is evacuated from within the packaging tray cavity through perforations and/or incisions in the tray wall at first and second incision sections 826 and 828 into space 860 and 858, created when the flap is placed adjacent the tray wall, the air flows through apertures 854 when the tray wall 817 is distended, and then the flow path follows into apertures 818 in the outer cover 816. A suitable gas or gas blend such as nitrogen and carbon dioxide can then be provided into the vacuum chamber. The desired gas can be provided in a reverse flow direction into the finished packages by way of direct communication through apertures 818, apertures 854 into spaces 860 and 858, through perforations at incision sections 826 and 828 and thereby fill all free space within the finished packages in the gas barrier master container. A gas barrier lid can then be hermetically heat sealed to the opening of the gas barrier master container and the finished packages in the hermetically sealed master container can then be stored at a controlled temperature for a desired period of time prior to opening the master container and removal of the finished packages for retail sale. In this way air and gases can be removed from the finished and sealed packages by evacuation and then replaced by gas flushing with a desired gas, while liquids such as blood cannot readily escape.

[0582] 3.2.8. Embodiment

[0583] Another embodiment of a tray with flaps is shown in FIGS. 33-37. Tray 900 includes flaps 906, wherein the flaps can be folded to lie in an adjacent position to tray sidewall 925. The flap 906 includes a first 907 and a second 909 ridge with a depression 911 spanning therebetween. The face on opposite side of the depression 911 is not in touching proximity with the tray sidewall 925, thus providing gap 926 between the flap 906 and the tray wall 925. The flap 906 is in a folded down position and a gap 926 is arranged between openings 928 and the tray side wall 925. The shrink film 920 holds the flap 906 firmly and tightly against the tray wall 925. An adhesive such as a cold seal latex, or any other suitable adhesive may be provided between the flap 906 and the tray walls 925 so as to cause sealing and bonding where contact between the flaps and the tray walls occurs.

[0584] FIG. 34 provides details of a cross-section through a section of the tray wall and the flap when in direct contact with each other. It is to be appreciated that a flap is an extension of the material that similarly forms the tray body, however, in this instance the exterior of a tray wall will be bonding to a flap that has been folded over so that similar materials are bonded to one another. In one instance, a material or “skin” 934 is shown on the outer surfaces of the section directly adjacent to EPS foam 936 that is bonded together by adhesive layer 946 causing a secure bonding and sealing of the tray wall and the flap together. The sealing and bonding can be arranged so as to provide a completely sealed and “liquid tight” condition such that any liquids contained in the spaces 930 and 932 will be retained within the spaces.

[0585] Referring now to FIG. 35, an elevation of a finished package 918, is shown. The finished package 918 includes a packaging tray as shown in FIG. 33 with perishable goods located in tray cavity with an outer cover 920. The outer cover 920 includes an envelope of material that completely covers and encloses the packaging tray and the perishable goods therein. The outer cover 920 is heat sealed to provide a sealed package. The outer cover 920 may be manufactured from a shrink material such as Clysar, manufactured by DuPont, or alternatively a stretch wrapping material such as Mapac -M, a plasticized polyvinyl chloride web material manufactured by AEP Industries, Inc. The outer cover 920 can be printed such that all surfaces are rendered opaque leaving a transparent window 922 on the upper surface as shown in FIG. 35. Clysar outer cover shrink material is then heat shrunk such that the outer cover shrinks, holding flaps against the tray walls. Alternatively, if the Mapac -M, pPVC material is used, heat shrinking may not be required and the Mapac -M material is stretched over the tray with flaps such that flaps contact the tray walls. In one aspect, apertures 924 are provided on the four vertical faces of the finished package. The apertures 924 are conveniently located in such a location so as to minimize the probability of any liquids, such as blood or “purge”, escaping therethrough. For example, apertures 924 can be provided in the space created by the first ridge 907 as shown in FIG. 33.

[0586] Referring now to FIG. 36, an enlarged view of a cross section of the tray of FIG. 33 is shown. The flap 906 and the tray wall 925 are in some areas in intimate contact with each other. The gap 926 is arranged between openings 928 and the tray side wall 925. Spaces 930 and 932 created by the ridges 907 and 909 and the tray side wall 925 are directly adjacent to incision sections 918 and 916. A suitable adhesive can be applied between the flap 925 and the tray at all direct points of contact therebetween causing a secure bonding and sealing of the tray and the flap 906 together. The sealing and bonding can be arranged so as to provide a substantially sealed and “liquid tight” condition such that any liquids contained in spaces 930 and 932 will be retained. The shrink film, outer cover 920 holds the flap 906 firmly and tightly against the tray wall 925. Referring now to FIG. 37, a cross-section of the tray base portion 938 and the outer cover 920 are shown to be in adjacent disposition. An adhesive layer 948 can be provided so as to completely bond the outer cover 920 to the base of tray 938.

[0587] Furthermore, when the outside-surface of foam is arranged to have a capacity to absorb liquids, such liquids can be retained and substantially prevented from escaping from within the finished package. Additionally, a suitable adhesive can be provided between the tray flange rim 944 and the outer cover 920 where the continuous flange rim 944 is in contact with the outer cover 920 so as to cause bonding in a substantially liquid tight fashion therebetween. The openings at incision sections 916 and 918 in the tray wall 925, openings 928 in the flaps and apertures 924 in the outer cover 920 provide a passage and direct communication from the tray cavity to the outside of the finished package such that when the finished package is exposed to a vacuum, air and gases can be removed from within the package and replaced with a desired gas or mixture of gases through the passage.

[0588] 3.2.9. Embodiment

[0589] Referring now to FIG. 38, another embodiment of a packaging tray with flaps constructed according to the present invention is shown. The packaging tray 1000 of this embodiment as with the packaging trays of previous embodiments is similar in operation, but with an alternate configuration of the channels through which evacuation and flushing is accomplished.

[0590] FIG. 38 shows detail of the packaging tray with flaps extended and including a tray with tray cavity and four flaps shown as flap 1002, flap 1004, flap 1006, and flap 1008. Flap 1002 is provided with a profile that mirror images flap 1006, and flap 1004 is provided with a profile that mirror images flap 1008. Flaps 1002, 1004, 1006 and 1008 are attached to the outer edge of flange rim 1010 at hinges 1012 as shown, such that flaps 1002, 1004, 1006 and 1008 will fold downwardly and intimately contact outer surfaces of the tray walls. FIG. 39 shows the packaging tray with flaps folded downwardly. The cross-sectional profile of flaps 1002, 1004, 1006 and 1008 are similar. Flap 1002 and flap 1006 being of substantially similar dimensions, and flap 1004 and flap 1008 being of substantially similar dimensions, but can be longer or shorter than flaps 1002 and 1006. Referring yet again to FIG. 38, the packaging tray 1000 includes a base with four upwardly extending tray walls terminating at a continuous flange rim 1010. The tray walls can be perforated with openings directly therethrough with the perforations arranged in sections shown as a first incision section 1014 and a second incision section 1016. The perforations may be in the form of small holes or incisions that extend fully through the tray walls, but are substantially provided within the limits of regions shown as first and second incision sections 1014 and 1016, respectively. Flaps 1002, 1004, 1006, and 1008 have a generally planar surface 1001 with two end walls 1003 that gradually increase in width from the flange rim 1010, so as to have their greatest width at the flap base 1005, thus, forming a substantially triangular appearance. The flap base 1005 connects the flap face 1001 the two flap end walls 1003 to a flap flange which forms a periphery around the flap end walls and flap base. The underside of the flap flange 1007 provides a suitable sealing surface for bonding to the tray 1000 thereto. This structure of flaps, thus creates a space between the flap face 1001 and the tray walls when the flaps are in a folded position as shown in FIG. 39. Apertures provided in sections 1014 and 1016 provide communication into the spaces formed between the flaps and tray walls. Apertures 1020 formed on the flaps provide a passage from the spaces formed between the tray flaps to the exterior of the tray as shown in FIG. 39. The combination of apertures 1014, 1016, and 1020 provide for evacuating and flushing the tray, for example, as in a master container.

[0591] 3.2.10. Embodiment

[0592] FIGS. 40-42 show yet another embodiment of a tray with flaps constructed according to the present invention. The tray 1100 of this embodiment is similar in operation to the trays described above. Referring to FIG. 40, a tray is shown whereby flaps 1102 and 1106 can be arranged so as to have no openings therein, and flaps 1108 and 1104 can be arranged to have openings 1110 therein. Tray 1100 as shown in FIGS. 40-44 can be over wrapped with a web of pPVC to produce a finished package. The web of pPVC can be printed on the inner surface with a heat activated coating that can provide a method of bonding the web of pPVC to faces 1112 on flaps 1102 and 1106 and face 1114 on flaps 1100 and 1104. The heat activated coating can be applied to the web of pPVC by typical offset printing process and applied in those areas of pPVC that will come into contact with the faces 1112 and 1114 after over-wrapping the tray 1100 with the web of pPVC in such a manner that when heat is applied to the pPVC, in contact with the faces 1112 and 1114 the web of pPVC will become bonded to the faces 1112 and 1114. The web of pPVC will thereby cover recess 1116 and recess 1118 in flaps 1108 and 1104 but will not fully enclose and isolate the recesses leaving openings at openings 1120. The web of pPVC can also thereby cover recess 1122 and recess 1124 in flaps 1106 and 1102 but will not fully enclose and isolate the recesses leaving openings at openings 1126. In this way, a path of direct communication from internal space of the tray to external atmosphere is provided through apertures 1128 in tray base into space 1130 (shown in FIG. 44) through apertures 1110 in flaps 1108 and 1104 only, and then into recesses 1116 and recesses 1118 and through openings 1120 into the space between the pPVC outer cover and tray through space 1131 (shown in FIG. 44) and therefrom through openings 1126 into recesses 1124 and 1128 and finally through apertures 1133 (shown in FIG. 44) that are provided in the outer cover 1135 pPVC adjacent to the recesses 1122 in flaps 1102 and 1106 to external atmosphere shown in FIG. 44.

[0593] The tray 1100, as well as any other tray herein described, may be thermoformed from any suitable material such as expanded polystyrene EPS materials as shown in FIGS. 231-239. The EPS materials may include several layers of co-extruded material that are arranged so as to allow any liquids that may enter space 1130 of FIG. 44 through apertures 1128 to be absorbed into the open cell structure of EPS materials through surface perforations 1150 that can be provided into the surface of the EPS materials that are adjacent to space 1130. Liquids can thereby be concealed within the layers.

[0594] The pPVC outer cover 1135 can be bonded to the underside of the tray 1100 by any suitable method, such as heat sealing or adhesive bonding, so as to follow contours of recess 1132 shown in FIG. 41. The pPVC outer cover can also be bonded, by any suitable method, such as heat sealing or adhesive bonding, to flange rim 1134 along the full length and perimeter thereof so as to inhibit liquids from passing between the flange rim 1134 and the pPVC over wrapping web of material after the bonding. In this way liquids that may accumulate in internal space of tray are restricted from escaping from within the finished package, while providing a path to allow extraction and injection of suitable gases into and out of the internal space of tray.

[0595] Another embodiment of the tray according to the invention has flaps as shown in FIG. 45, wherein flaps 1256 and 1258 include flap bases 1257 and 1259, respectively that extend below the lower surface of the tray base. The upper surface of the flap base 1257 and 1259 can therefore be bonded to the underside of the tray base. In this manner, the flaps 1256, 1258 provide additional cushioning around the lower perimeter of the tray 1200. The additional cushioning can provide protection of the package and the package contents during shipping from the point of production of the finished packages and to a point of sale to consumers such as a supermarket.

[0596] 3.2.11. Embodiment

[0597] Referring now to FIG. 46, another embodiment of a packaging tray 1300 with flaps constructed according to the present invention, is shown. The flaps are shown folded into a desired position and bonded to the tray base and/or walls. The packaging tray with flaps can be thermoformed from suitable plastic materials such as polystyrene, polyester and polypropylene in a solid or foamed sheet. The present packaging tray is preferably thermoformed from expanded polystyrene (EPS) sheet. The EPS sheet may include a single or multi-layer construction as shown in FIG. 50. Any suitable sheet of EPS material may be used. A suitable sheet includes three layers 1304, 1306, and 1308. The layer 1304 includes a layer of solid plastic material such as polystyrene sheet with any suitable thickness, about 0.001″ and is laminated to layer 1306. Layers 1306 and 1308 include “closed” or “open cell” structures either with or without a surfactant added prior to extrusion of the sheet such that the finished tray may have a capacity to absorb water and other liquids such as “purge” or blood. The EPS sheet may be extruded with a “skin” covering on a surface that will become the inside of the finished tray. The “skin” can be arranged so as not to absorb the liquids. The non-absorbent “skin” may be provided on both surfaces of the extruded sheet. The layer 1304 may contain a white or other suitable pigment, such as white titanium dioxide in such a quantity so as to prevent visibility of any discoloration that may be caused by blood or purge absorbed by layers 1306 or 1308. In this way, the layer 1304, which will be visible, will not show substantial discoloration as a result of blood or purge that has been absorbed by any of the other layers.

[0598] Tray 1300 with flaps is thermoformed from sheet material of suitable thickness, about 0.01″ to about 0.15″ but sometimes about 0.090″ and includes a tray with a tray cavity and four flaps. Two flaps are shown as flap 1310 and flap 1312. Flap 1310 is an end flap and flap 1312 is a side flap. The construction of tray 1300 with folded and bonded flaps, allows for production of rigid finished trays even though the thickness of the sheet material from which the tray is formed, is substantially thinner than would otherwise be required in conventionally formed packaging trays that do not have “flaps”.

[0599] Flap 1310 can be provided with a profile that is a mirror image of 1314 (not shown), and flap 1312 can be provided with a profile that is a mirror image of flap 1316. Flaps 1310, 1312, 1314 and 1316 are attached to the outer edge of flange 1318 at hinges as shown by the hinge lines, such that flaps 1310, 1312, 1314 and 1316 can be folded downwardly and intimately contact outer surface locations of the tray walls as required. One or more flaps may be provided and folded to provide a plurality of enclosed spaces 1322 and/or cavities 1320 shown in FIGS. 49 and 47, respectively. The cross-sectional profile of flaps 1310 and 1314 can be similar. The cross-sectional profile of flaps 1312, and 1316 can be similar.

[0600] Referring again to FIG. 55, the packaging tray 1300 includes a base with four upwardly extending tray walls terminating at a continuous flange 1318. Tray walls can be perforated with openings 1324 directly therethrough with the perforations arranged so as to communicate between the tray cavity and space 1322 shown in FIG. 49. Referring to FIG. 49, the apertures or openings 1324 can be located so as to allow any purge that may be present in the tray cavity 1326 to pass therethrough and into space 1322. The perforations 1324, may include small holes, slots or incisions that extend fully through the tray walls. The flaps can be bonded to the tray walls so as to retain any liquids that enter therebetween and into space 1322.

[0601] In a further aspect of the present invention, any suitable liquid absorbing medium may be attached to one or more of the flaps so that when the flaps are folded and bonded the liquid absorbing material will be enclosed within space 1322. The liquid absorbing material could therefore absorb any liquids that may enter the space 1322 during use of the tray.

[0602] Referring again to FIG. 46, recesses 1328 and 1330 are shown in flap 1312. Slots 1332 are shown in flap 1312 and are located in recess 1328. Perforations 1334 are provided in flap 1312 and are located in recess 1336 (see FIG. 47). Recesses 1338 and 1340 are shown in flap 1310. A suitable adhesive is provided at the interface between the flaps and the tray walls so as to provide a bonding of the flaps to the tray walls. Bonding of flaps and tray walls is provided in such a manner so as to ensure complete bonding of flaps to the tray wall along strips that follow a path close to the perimeter of the flaps.

[0603] FIG. 49 shows a cross-section through flap 1312 and tray wall showing enclosed space 1322. Space 1322 is enclosed between the flap and the tray wall in a substantially liquid tight manner. Iron powder deposits 1344 can be applied to locations on the tray walls and flaps within space 1322 and also to the underside surface of the tray base. The iron powder deposits 1344 may include iron powder particles that have been fully coated with a special coating material, such as wax. The coating can be arranged to prevent direct contact of the iron particles with ambient air or any gas that may be present, until such direct contact with the air or gas is required. The coating may have physical and/or chemical properties that can be activated by exposure to microwaves, radio waves or a magnetic field. For example, when using wax as a coating, microwaves will cause the iron particles to heat up, thereby melting the wax and exposing the iron particles. The coating may also contain an adhesive that is heat activated and otherwise does not bond with other matter until activated and/or heated by exposure to any suitable microwaves, radio waves, magnetic field or any suitable electrically or sonically induced waves or field. The coated iron particles 1344 can be deposited on the surfaces by apparatus described herein. The coated particles can be coated with a substantial gas barrier substance that is altered when exposed to suitable microwaves or an electrically induced magnetic field. Exposure to the waves, field, or microwaves can cause the coating gas barrier substance to physically or chemically alter and become gas permeable, in such a manner that will cause the iron particles to immediately or subsequently react with any gases such as oxygen that may be present. The quantity of iron particles 1344 provided and attached to selected surfaces of the tray and flap can be measured and controlled so that an amount is present having an equal or greater capacity than may be required to absorb substantially all oxygen gas that may be present and/or become present by permeating into the finished package. While a cross-section of flap 1310 is not included with this embodiment, flap 1410 of tray 1400 (discussed below) has substantially similar features and will be discussed in detail later in this application.

[0604] Referring now to FIG. 47, a top cross-sectional view through tray wall and flap 1312 is shown. For illustration purposes, a section of web material 1346 is shown bonded to plane 1348. Recesses 1336 and 1330 are therefore shown as enclosed channels. Cavity 1320 is fully enclosed by bonding at interface 1342 and sealed from external communication save through perforations 1334. Gases can therefore communicate through the perforations 1334 between the cavity 1320 and recess 1336. The gases can therefore come into direct contact with deposits 1344 deposited on the sides of cavity 1320. The deposits 1344 are suitably applied to tray and flap surfaces that will not come into contact with any goods that are subsequently located in the tray cavity.

[0605] Turning to FIGS. 46, and 48-49, a further aspect of the present invention is shown therein. A cross-sectional view through crest 1350 is detailed in FIG. 48 with hinge 1352 between the flap 1310 and flange 1318. In FIG. 49, tray 1300 is shown in a horizontal disposition with the opening in tray cavity facing upwardly. The tray base is profiled so as to be higher at the center of the tray base than at the lowest point of the tray cavity (at a radius connecting the tray base to the upwardly extending tray wall) and a clearance, designated by arrow 1354 is shown. The clearance 1354 is the distance (clearance) measured from the lowest point of the tray 1300, at the side flaps and the highest point of the under surface of the tray base. The clearance 1354 is arranged so as to suitably accommodate and “mate” with the crest 1350 when another tray (not shown) is located above and placed onto a lower tray 1300. In another alternate, the clearance 1354 may be enclosed by over wrap material to provide a cavity into which purge may enter through suitably located apertures in the tray. Suitable liquid absorbing material with a suitable capacity may be provided between the over wrap and underside of the tray base. The crest 1350 and clearance 1354 prevent the base of a stacked tray from contact with an overwrap on the bottom tray. In this manner, the goods are prevented from touching the base of an adjacent tray.

[0606] 3.2.12. Embodiment

[0607] Referring now to FIGS. 51-52, another embodiment of a tray 1400 with flaps similar to tray 1300 is shown. Tray 1400 with an interior cavity and flaps that are substantially similar to the flaps of tray 1300 therein is shown after over wrapping with overwrap web 1402. Web 1402 may be formed from a plastic material, such as pPVC. The tray depression may be substantially filled with goods such as ground beef prior to over wrapping with the over wrap 1402. Over wrap 1402 may be stretched in such a manner as to contact the goods in the cavity. The web of material 1402 may be printed with information that gives detail of the contents of the over wrapped tray. Furthermore the inner surface of the over wrap 1402 may have been processed and a heat activated coating applied thereto, by any suitable method, and in those areas that will come into contact with surfaces of the tray 1400 and the flaps 1412, 1410, 1416 and 1414. Because flap 1416 may be a substantial mirror image of flap 1412 and flap 1414 may be a substantial mirror image of flap 1410, only flaps 1412 and 1410 will be discussed. But it is appreciated that substantially similar features are present that operate in substantially the same manner along the flaps that are mirror images of those discussed. A suitable heat source can be provided to activate the heat activated coating so as to cause bonding of the web 1402 to flaps 1412 and 1410 along planes contacting portions of the flaps at 1458, 1460, 1456, and 1498 locations shown as shaded sections. Alternatively, the shaded areas shown as 1458 and 1456 may be coated, by any suitable method, such as by “ink-jet”, with any suitable bonding material such as a heat activated coating. Apertures 1496 may be provided as shown. Apertures 1496 can be provided after bonding of the web to plane 1456 such that communication directly into recess 1438 (shown in FIG. 52) is provided.

[0608] A cross-sectional view of flap is shown in FIG. 52 through where web 1402 has been bonded to plane 1456 thereby providing space 1462 and recess 1464. Apertures 1466 in flap, apertures 1424 in wall of tray and apertures 1496 in web 1402 are provided. In this manner, a communication is provided between the tray cavity to the outside of the over wrapped tray following a path that will readily allow gases to communicate therethrough but will restrict escape of liquids, such as purge. The communication follows a path through aperture 1424 into space 1468, through aperture 1466 into recess 1464, through recess 1464 to space 1462, through space 1462 to recess 1440, through recess 1440 to recess 1438 and through apertures 1496.

[0609] Referring now to FIG. 53, a stack of 4 finished packages of the tray 1400 shown in FIG. 51 is shown. A cross-sectional view is shown in FIG. 54, through the stack of packages. It can be seen that with this arrangement an upper tray is in contact and rests on the flange of a lower tray. As can also be seen, if clearance is provided in the underside of the base of tray, the clearance mates with the upper profile of a lower tray whereby the contents of a lower tray are located in close proximity to the upper tray but are not in contact with the underside of the upper tray.

[0610] Referring now to FIG. 55, a finished package 1400 is shown with a seal 1470, that extends continuously around a horizontally disposed perimeter of the finished package. Seal 1470 is provided so as to bond an over wrap 1472, which is positioned above the seal 1470, to an over wrap 1474 which is located below the seal 1470. The seal 1470 can be provided by any suitable method such as by heating, and is arranged to be a complete and continuous and gas tight seal along the full length of the tray. The over wraps 1472 and 1474 may be clear, transparent, or printed as desired. Overwraps 1472 and 1474 may be produced from a substantial gas barrier material such that when sealed along seal 1470, a hermetically sealed finished package is produced. Alternatively gas permeable plastic materials may be used to produce the over wraps. The profile of over wrap 1472 and 1474 may be provided by a thermoforming method prior to assembly of the finished package whereby a loaded tray 1400 is located into a thermoformed over wrap 1474 prior to sealing to the thermoformed over wrap 1472 thereto at seal 1470. Alternatively, both over wraps 1472 and 1474 may be produced from a web of “stretched” material such as pPVC. The web of pPVC may be held taut above the tray cavity where the cavity is similar in profile to the lower section of tray 1400 but slightly larger so as to allow a neat location of tray 1400 therein. A vacuum can be applied in the cavity so as to stretch the pPVC web therein and thereby provide a lower over wrap 1474. Tray 1400 can be located into the stretched pPVC depression and heat sealed at 1470 to an over wrap 1472 that can be formed in a similar manner by stretching into an inverted cavity, of suitable size, that is located directly above and aligned therewith so as to allow such sealing at seal 1470. Apertures 1496 may be provided in the over wrap 1474 or alternatively, over wrap 1474 may be maintained without apertures so as to provide a substantially gas barrier package (similarly to tray 1300 in FIG. 49).

[0611] 3.2.13. Embodiment

[0612] Referring now to FIG. 56, a further embodiment of a packaging tray with flaps, constructed according to the present invention is shown. FIG. 56 shows a tray 1500 with a flap 1502 attached to a flange 1506 of the tray 1500 by a hinge 1504. Tray 1500 can also be provided with similar flaps attached by hinges to all four sides of the tray at hinge lines between flaps and flanges. However, FIG. 56 shows a tray that has two flaps, on opposing sides, where one only flap is visible.

[0613] Packaging tray 1500 includes a substantially flat base that may have depressions, ridges, apertures and/or penetrations provided therein, with upwardly extending walls terminating at a continuous flange 1506. A ledge 1508 is provided in two of the four walls in a horizontally disposed position and level, across the face of the side wall and between the flange and the base of tray. The other two walls have flaps 1502 attached thereto, at a hinge 1504 connecting the flaps to the flange. Apertures 1510 are provided in ledge 1508. Apertures 1512 are provided in flaps at optimized locations that will reduce the passage of solid or liquid matter therethrough. An alternative and or additional aperture construction is also shown as slot 1534 cut through a compressed section 1540 of tray 1500 in cross-section FIG. 59 and in an enlarged view, FIG. 60, showing details of the slot 1534 provided in a section of the flap along ridge 1514. Slots may also be located at other locations shown in the FIG. 56. The region surrounding the slot is compressed to provide a section of thinner cross-sectional material. Slot 1534 includes an incision in the compressed section 1540 of the ridge 1514 and may be provided with an “H” profile. The slot 1534 with “H” profile provides two adjacent flaps, 1536 and 1538, respectively, that can open when, a differential in gas pressure is provided on opposite sides of the flap, however, when the gas pressure differential has equalized the two adjacent flaps shown as “H” flaps, can close to the former condition before opening.

[0614] Flaps 1502 are folded downwardly, against the upwardly extending adjacent tray walls 1516 as shown in end view of flap in FIG. 57, prior to over wrapping. Flaps 1502 can be provided with a fastening lug 1542 that is profiled so as to “mate” with a corresponding fastening recess 1544 provided in tray 1500. The fastening lug 1542 and fastening recess 1544 hold flap 1502 in a downwardly located position in convenient readiness to be inserted into a bag prior to sealing and shrinking. FIG. 58 shows an alternate of flap 1502, wherein fastening lug 1542 on flap 1502 and fastening recess 1544 on tray 1500 have been removed providing a substantially flat surface profile for contact with the tray walls 1516. Flaps 1502 may otherwise prevent automated loading of the tray with perishable goods therein, into the bag.

[0615] In this way, substantially all atmospheric air can be removed from within the finished packages via a route that follows a path through apertures 1510 (FIG. 56) into space 1528 (FIG. 57), through apertures 1512 (FIG. 56) into space 1522 (FIG. 57) and through apertures 1520 (FIG. 57) in the over-wrap material.

[0616] 3.2.14 Embodiment

[0617] Turning now to FIG. 61, a cross sectional view of another embodiment of a packaged tray 1500 according to the invention is shown. Flap 1502 is provided with a continuous rim flange 1506. The continuous rim flange 1506 is provided in such a manner so as to contact the inner surface of the outer cover 1550. Rim flange 1506 is in continuous contact around the perimeter of the flap 1502 and substantially restricts passage of matter between the rim flange 1506 and the outer cover 1550 as shown in FIG. 61.

[0618] The tray 1500 with flaps 1502 is shown after outer cover 1550 has been heat shrunk into a finished position. Apertures 1520 are provided in the outer cover 1550. A space 1522 is provided between the flap and the outer cover such that apertures 1520 provide direct communication between the space 1522 and external atmosphere. Flap apertures 1512 provide communication from space 1522 to space 1528 and tray wall apertures 1527 provide communication from space 1528 to the tray cavity.

[0619] While the embodiment of tray 1500 shown in FIG. 61 contains tray wall apertures 1527, it is apparent to one of ordinary skill in the art that the tray wall 1516 could include a flange 1508 containing apertures 1510 as shown in FIG. 56. The aforementioned configuration could provide a means of communication between the space 1528 and the tray cavity. A perspective view of the finished package 1580 is shown in FIG. 62.

[0620] Referring again to FIG. 61 and FIG. 62, it can be understood that when a plurality of finished packages are assembled in a stack, the base of tray 1500 with adjacent flaps will be in intimate contact with the upper surface of the finished packages. The flaps 1502 will be in adjacent contact with a portion of the rim flange regions 1506 of the lower package, thereby supporting the weight of packages stacked above. Therefore, the perishable goods contained in any package located beneath a package stacked above, will be protected from damage.

[0621] 3.2.15. Embodiment

[0622] Referring now to FIG. 63, another embodiment of a tray flap constructed according to the present invention is shown. FIG. 63 shows a cross-sectional view through tray 1600 detailing the profile of flap 1602. Rib 1620 is formed in flap 1602 adjacent to recess 1624. Rib 1620 is formed so as to contact wall of tray as shown when flap 1602 is folded into a downward position. Recess 1624 is formed in the flap 1602 with an aperture or slot (not shown) therein but does not contact the outer surface of the wall of tray and is provided with space 1628 therebetween. A suitable adhesive such as a solvent is applied to the surfaces of the flap 1602 and the wall of tray such that when flap 1602 contacts the wall of tray, both parts bond together. The bond between the flap 1602 and the wall of tray can be arranged to follow a continuous path close to the perimeter of the flap 1602 and thereby provide a substantially liquid “tight” seal around space 1628. Adhesive can be applied to flaps in a similar manner to that described for flap 1602 then, in like fashion, bonded, to walls of tray to produce a finished tray. Apertures 1630 can be provided in the lower section of the wall of tray such that liquids that may accumulate within the tray can pass through apertures 1630 and enter space 1628. Slots, slits or holes (not shown) can be provided in recess 1624 such that direct communication through recess 1624 into space 1628 and through apertures 1630 can be provided. The surface of the flap and the wall of tray in direct contact with space 1628 can be treated so as to absorb liquids such as water, purge and blood.

[0623] Flap 1602 also includes a leg 1640 similar to the leg used in tray 900 (FIG. 33). The leg 1640 may be received into a recess 1619 formed in the base of the tray 1600. Alternatively, a support leg 1615 may be formed in the base of the tray that extends downwardly from the base. When the support leg is positioned at a sufficient distance from the wall of the tray, the leg 1640 may be received into the area along the base of the tray between the wall of the tray and the support leg 1615.

[0624] As with many of the similarly designed trays, the leg 1640 of the flap 1602 will be in intimate contact with the top flange 1606 of a tray beneath when trays 1600 are stretched.

[0625] 3.2.16. Embodiment

[0626] Referring now to FIGS. 64 and 65, another embodiment of a tray with flaps constructed according to the present invention is shown. A cross-section view through a finished package in shown in FIG. 64 and a three dimensional view of a finished package 1702, is shown in FIG. 65. The finished package 1702 includes a tray 1700 with perishable goods contained therein and an outer cover 1704 of a substantially gas barrier shrink material. Apertures 1706 are provided in the gas barrier outer cover 1704 and a peelable, gas barrier label 1708 is hermetically sealed over the apertures 1706. The finished package 1702 has spaces 1710, 1712 and 1714 and other space contained within the outer cover 1704. Apertures and passages have been provided in the flaps and tray walls as herein described. A substantially oxygen free gas including any suitable gas, selected to extend the keeping qualities of the perishable goods, such as a blend of carbon dioxide and nitrogen, can be provided in the spaces inside the package 1702 after evacuating other gases contained therein, such that all the spaces are filled with oxygen free gas. The finished package can be stored for a period of time and then, using tab 1714, the gas barrier label 1708 can be removed by peeling, thereby allowing atmospheric gas to enter through the apertures 1706 and into the spaces around the perishable goods and contact the perishable goods, thereby causing a desirable bloom in the goods. In a further aspect, a ridge 1715 is provided in the flap 1717 to abut against the outer cover 1704. The ridge 1715 provides a suitable structure against which to apply a label 1708.

[0627] 3.2.17. Embodiment

[0628] Referring now to FIG. 66, another embodiment of a finished package constructed according to the present invention is shown. A cross-sectional view with details of a tray 1800 with flaps that are folded into the finished position and extend below the base of tray is detailed. As described in earlier embodiments of this present specification, a tray with flaps may include a rectangular flat base with radiused corners and upwardly extended walls that terminate at a flat horizontally disposed, common peripheral flange. A space or cavity is therefore defined between the walls. Flaps are connected directly to the peripheral edge of the common peripheral flange at a hinge along a hinge line. A single flap may be attached to a single wall or alternatively up to four flaps may be attached, one to each wall. It may also be desirable to attach several flaps to a single wall. Flaps and trays of various configurations have been described herein with apertures conveniently provided to allow gas or air exchange therethrough while inhibiting and restricting the escape of other matter such as liquids including blood or purge therethrough. Such apertures and configurations allowing gas exchange therethrough can be provided in this present embodiment if desired, however, the purpose of the description of this present embodiment is to disclose an improved packaging that will also protect the perishable goods contents of the finished package when stacked together, such as when placed in a master container.

[0629] Referring now to FIG. 66, a loaded tray 1800 with flaps 1802 is completely covered with an outer cover 1804 and it can be seen that the outer cover 1804 is domed upwardly and is stretched over the upper surface of the perishable goods 1806 such that the uppermost part of the perishable goods 1806 is extended above the common peripheral flange 1808 under the outer cover 1804. In this manner the perishable goods 1806 are held firmly to the base 1810 of tray 1800 by applying tension on the outer cover material. An adhesive 1812 may be provided between the outer cover 1804 and the common peripheral flange 1808 so as to seal, hermetically or otherwise, the outer cover 1804 to the common peripheral flange 1808 along a path that will become an outer edge of the finished package. Additionally and as shown, adhesive 1812 may be provided between the flaps 1802 and the tray walls 1814 so as to seal the flaps 1802 in position to the walls as may be desired, hermetically or otherwise. Adhesive 1812 may also be provided between the underside of the base 1810 and between the base and the inner surface of the outer cover 1804. Outer cover 1804 may include a suitably printed, heat shrinkable, stretchable, sealable, transparent, oxygen and gas permeable web of material with a “memory” that may be applied after loading the perishable goods into the tray cavity. The outer cover 1804 may be applied directly from a continuous web or roll of the material or alternatively may be fabricated into suitably sized bags, such as those supplied by Robbie Manufacturing, Inc., prior to sealing over the loaded tray with flaps. As shown in FIG. 67, the outer cover 1804 may be suitably perforated with apertures 1805 to allow gas and/or air exchange therethrough and can be heat shrunk after sealing over the loaded tray with flaps by passing through a suitably adjusted heat tunnel. Alternatively, in another aspect of a packaging tray, the outer cover 1804 may be applied from a continuous web and stretched during application thereof and then sealed to provide a sealed outer cover 1804 that is stretched taut around and over the loaded tray with flaps as shown in FIG. 66.

[0630] FIG. 68 shows a cross-section of a tray after the application of the outer cover 1804, that may be manufactured from any transparent suitable material, but before stretching by depressing the outer cover 1804 into the recess 1816 as shown in FIG. 69. FIG. 69 shows the same cross-section as in FIG. 68 after outer cover 1804 has been depressed so as to contact the adhesive between the base of tray 1800 and the inner surface of the outer cover 1804. By a mechanical device, the outer cover 1804, that is located adjacent to the underside of the base 1810 of the tray, can be depressed and stretched so as to contact the adhesive 1812 located between the inner surface of the outer cover 1804 and the under surface of the base 1810 of tray so as to provide bonding therebetween. A recess 1816 can therefore be provided on the underside of the tray 1800 as shown. Therefore, when another finished package of similar configuration is located and stacked above and onto a similar lower package, the underside of the finished package will not contact the upper surface of the dome of the lower package. In this way, the lower packages are protected from damage when stacked and transported or when displayed in stacks at a point of sale to consumers.

[0631] 3.2.18. Embodiment

[0632] Referring to FIG. 70, another embodiment of a tray 1900, with flaps 1902, 1903 is shown. A cross-section is shown in FIG. 71, where both flaps are folded inwardly and the package has been inserted into a suitable shrink bag 1914. Alternatively, the shrink bag 1914, may be replaced with a stretch wrap material such as plasticized PVC. In this manner, the tray can be “stretch-wrapped” as an alternate to a shrink bag as shown in FIG. 71.

[0633] Tray 1900 includes a base with four upwardly extending walls, terminating at flanges 1904. Two flaps 1902, 1903 are provided such that they can fold inwardly. Recesses 1906 are provided in the flaps to allow passage of gases therethrough. Tray 1900 further includes a base rim 1908 shown in FIG. 71 that extends around the perimeter of the base. Depressions 1910 and perforations 1912 can be provided at the tray base 1926. Apertures 1916 are provided in shrink bag 1914. Tray 1900 may be thermoformed from any suitable material. Apertures 1916 provide direct communication from external atmosphere through space 1918 and recesses 1906 to tray cavity. Perishable goods can be located in tray cavity and flaps 1902 and 1903 folded inwardly. Assembled tray and perishable goods can then be located within a shrink bag, which is then heat sealed and heat shrunk or stretch wrapped. When the finished packages are stacked, the base rim 1908 of one pack will rest directly above flaps 1902 and 1903. In this way, finished packages can be stacked together without causing undesirable damage to the contents of the packages. Perforations 1912 may cause the absorption of liquids into the tray material as described herein.

[0634] 3.2.19. Embodiment

[0635] Referring now to FIG. 72 an isometric projection of a finished package 2002 constructed according to the present invention is shown and a cross-section through an empty package 2002 is shown in FIG. 74. Tray 2000 is thermoformed from a suitable material such as expanded polystyrene. Flaps 2004, 2014 are connected to the tray by way of hinges 2006. Flaps can rotate about the hinges 2006 such that upper surface of flanges 2008 can contact directly and be in alignment with flanges 2010 of the flaps.

[0636] Referring now to FIG. 72, perishable goods, such as ground meat is located in tray 2000 and a web 2012 is positioned directly above and over the tray 2000 and perishable goods. Web 2012 includes a transparent sheet of a suitable material such as plasticized PVC that has been coated with a heat activated adhesive covering the areas of the web that will come into contact with flange 2008 thereby providing a method of sealing web 2012 to the flanges 2008. After the web 2012 has been heat sealed to the flanges 2008, the web 2012 is severed along the perimeter of flanges 2008. The web 2012 is hermetically sealed along the full flange extending around the perimeter of the tray. Flaps 2014 and 2004 can then be rotated about hinges 2006 and flanges 2010 of flaps and sealed to flanges 2008 of the tray 2000.

[0637] Turning now to FIG. 73, in an alternate embodiment of tray 2000, flanges 2016 and 2018 are formed into a portion of the end walls of the tray 2000. Web 2012 can be sealed to the flanges 2016 and 2018 as shown. Aperture 2020 can be provided in the location shown such that direct communication between the gas contained between the tray and the web 2012 and external atmosphere is enabled. The location of aperture 2020 inhibits the egress of any liquids that may accumulate within the package from escaping therethrough. Additionally or alternatively, aperture 2022 is also shown. A plurality of finished packages can be stacked together such that face 2024 formed in the walls of the tray 2000 near the base engages with face 2026 formed in the flap 2004. Such engagement of faces provides a secure method of stacking finished packages.

[0638] 3.2.20. Embodiment

[0639] Referring now to FIG. 75, another embodiment of a finished package constructed in accordance with the present invention is shown. The package 2100 includes a tray 2102 and a tray cover 2104. Cover 2104 has a window 2130 cut therein as shown and web 2132 is stretched taut and heat sealed to flange 2134. Tray 2102 and tray cover 2104 are hermetically sealed together at flanges 2136 and 2138. Walls of tray 2102 and the cover 2104 can be printed directly thereon with information describing the contents of the package with all legally required information, pricing, weight of contents and cost per unit weight, etc. Recesses 2140 (four) in ridge 2142 are provided to allow for evacuation of air from between stacked packages. Recesses 2140 can also provide for location of bands of printed paper that may provide further information and details of package contents.

[0640] Referring now to FIG. 76, a cross-section through the end section of two stacked and finished packages 2100 of FIG. 75 is shown. The perishable goods contents of the packages have been omitted for clarity. Face 2146 engages face 2148 in recess 2152 when finished packages are stacked. Engagement of the faces 2146 and 2148 urges ridge 2150 of the lower package outward. The weight of the upper package is thereby transferred through the walls of the lower tray cover while inhibiting the inward displacement of flange 2134. Such an arrangement minimizes the likelihood of undesirable pressure being applied to the perishable goods contents of the lower tray by depressing the flange 2134 downwardly.

[0641] FIGS. 77-79 show an enlarged section of flange 3134, including a plan view in FIG. 77, side elevation in FIG. 78, and a further end view, FIG. 79, is shown with grooves and slots that allow direct communication between the inside of the finished package and atmospheric gases outside the package. Web 2132 is heat sealed along a continuous seal path 2156 and intermittent seals 2162 are shown with slots 2158 therebetween. Slot 2160 is therefore in direct communication with slots 2158 and 2164 and grooves 2166. Apertures 2168 are located adjacent to slot 2160 and directly between continuous seal 2156 and intermittent seals 2162. The apertures 2168 extend through the web 2132 and into the slot 2160. Web 2132 can include a sheet of plasticized PVC and is tensioned prior to sealing as shown thereby providing a transparent cover across the Window. In this way direct communication from within the package to atmosphere is provided through apertures 2168, slot 2160, slots 2158, slot 2164, and grooves 2166, while minimizing the possibility of any accumulated liquids escaping that may be present within the package.

[0642] Turning now to FIG. 81, in another embodiment 2102, tray and tray cover 2104 may be integrally formed and connected by a hinge 2110 at one side thereof. Tray cover 2104 has a web 2132 bonded thereto. Three empty trays 2102 with web 2132 sealed to covers 2104 are shown stacked together in FIG. 80. A section through a finished package with goods is shown in FIG. 82. Ridge 2150 of cover 2104 suitably mates with a recess 2152 of an overlying tray.

[0643] Turning now to FIG. 83, three finished packages 2100 are stacked together within a flexible gas barrier container 2190, showing how ridge 2150 mates with recess 2152. A gas barrier lid 2192 is hermetically heat sealed to gas barrier container 2190 after substantially all air has been evacuated and replaced with a suitable gas that may be substantially oxygen free.

[0644] 3.2.21. Embodiment

[0645] Referring now to FIG. 84, another embodiment of a tray with flaps constructed according to the present invention is shown. Tray 2200 includes a first 2202 and second flap (not shown). Flap 2202 is attached to tray 2200 by hinge 2210. Ridges 2220 are formed in flap 2202 and corresponding ridges 2222 are formed in the tray wall such that when flap 2202 and tray 2200 are in contact, portions of ridges are also in contact. Web 2232 is heat sealed to flanges 2212 and 2214. Apertures 2292 and 2294 are provided in the web 2232 and flap 2202 such that when flanges of the flap and tray are parallel to each other and in closest proximity, apertures are in alignment providing direct communication from the interior tray cavity to the exterior atmosphere.

[0646] Concentric depressions 2296 are shown in FIG. 84. In another aspect of the invention, tray 2200 may be formed from a three layer construction of expanded polystyrene where the inner layer includes an “open” cell structure that will absorb liquids such as water and blood. The depressions 2296 provided on the inner surface of the tray 2200, may allow contact of liquids, that may be present in the tray 2200, with the inner cells of the tray material and allow absorption of liquids by the open cell structure.

[0647] 3.2.22. Embodiment

[0648] Referring now to FIGS. 85-87, another embodiment of a tray with flaps constructed according to the present invention is shown. FIG. 85 shows a cross-section through a plurality of like trays 2300, showing a stackable feature according to the invention. Trays 2300 are stacked in master container 2390 containing the finished packages 2300.

[0649] In another aspect, FIG. 86 shows a cross-section through a tray 2300 that contains ground meat with a web 2332 stretched over the ground meat and sealed to flanges 2306, 2308 and edge portion 2310.

[0650] Flanges 2306 are not shown in this cross-section, but it is apparent that flanges 2306 are substantially planar with flange 2308 and at a minimum along opposite edges of flap 2302. Furthermore, flanges 2306 are oriented in the same direction as the cross-section shown in FIG. 86. The flanges 2306 occur along the bottom edge of the side walls of the flap 2302. Vertically, nearest flange 2308 when the flaps are folded inward to partially cover the tray cavity. Because the flaps have sidewalls (some of which may be curved), the walls of flap 2302 define an interior cavity 2330. Sealing web 2332 to a portion of the wall or edge portion 2310, flanges 2306, and flange 2308 creates a second cavity or recess 2320.

[0651] Flanges 2306 may also occur at other locations along the length of the flap 2302 oriented in substantially the same direction. Adding additional flanges 2306 will cause the web 2332 to seal to the flanges 2306 and the flap edge portion 2310 in an alternating pattern. This pattern will create a series of recesses 2320 in the locations where the web 2332 is sealed to the edge portion 2310. However, where the web 2332 is sealed to the flanges 2306, no recesses 2320 will occur. Recesses 2320 are carved out of cavity 2330. The space behind the web 2332 (i.e., the remainder of cavity 2330) remains in communication over its remaining area. Therefore, gases and liquids that travel into recess 2320 and enter aperture 2322 may enter cavity 2330. If apertures 2326 are provided in the walls of the flap 2302 that define the cavity 2330 (see FIG. 85), the aforementioned gases and liquids could escape the interior of the tray via the aforementioned path and exit into the surrounding environment through the apertures 2326.

[0652] A flap 2302 is shown that has been severed from tray 2300 and web 2332 is also sealed to flap 2302. Flap 2302 and tray 2300 are therefore attached together by web 2332 and a gap 2324 is provided between flap 2302 and the tray 2300. An aperture 2322 is provided in web 2332 at flap 2302 portion and an aperture 2326 is also provided in web 2332 at tray portion. A space 2318 may be provided between the product and the tray wall. Directly above space 2318, an aperture may be provided in the web 2332.

[0653] In another aspect of the invention, severing of flap 2302 is optional. In this embodiment, flange 2308 is not severed. Instead, a hinge may be provided by compressing flange 2308 with a profile so as to facilitate easy hinging of flap 2302 and tray 2300 relative to each other. FIG. 87 shows an alternate embodiment of tray 2300. In this embodiment, the flap 2302 is not severed and the edge portion 2310 has a convex profile. Furthermore, flange 2316 has been added at the end of the edge portion 2310.

[0654] Returning to FIG. 86, flap 2302 is arranged such that it can be “hinged” about the gap 2324 such that flanges 2306 and 2308 contact directly with web 2332 material therebetween. Flanges can then be sealed together through web 2332 such that web 2332 material seals together in a desired manner. The apertures 2322 and 2326 are positioned such that they become aligned after sealing of the flanges. Web 2332 material is then most likely to become lightly bonded together around the perimeter of apertures 2322 and 2326. An adhesive may also be applied to the contacting surfaces of web 2332 around the perimeters so as to cause substantial bonding and providing a substantially liquid ‘tight’ seal there around so as to inhibit escape of any liquids therebetween. This arrangement provides a direct communication from space 2318 to any atmosphere external to the package, via apertures 2326 and 2322, space 2330, recesses 2320 and space 2326. The location of apertures, spaces and recesses are arranged such that any liquids (or solid matter) that may accumulate within the package are inhibited from escaping from space 2318. With this arrangement, gases can communicate directly between space 2318 and while liquids and other solid matter is substantially restricted and held within space 2330 or 2318.

[0655] Referring to FIG. 85, packages are stacked such that the ridges 2336 on the base of a first package “nest” adjacent to ridges 2338 of a second package. A space can therefore be maintained between the bottom of the first package and the web and contents of the second package.

[0656] 3.2.23. Embodiment

[0657] Referring now to FIG. 88, another embodiment of a tray constructed according to the present invention is illustrated. In this aspect, the tray may be used to provide a sealable web having a peelable barrier layer to expose a semi-permeable layer beneath. The tray 2400 includes flap 2402. Flap 2402 is attached to tray 2400 along an outer edge of tray flange 2406 and a further flap (not shown) can be attached to the outer edge along the opposite side of the tray 2400 which is parallel with the first flap and is similar in operation thereto. After sealing the first and second webs to flanges 2406 and 2408, flap 2402 can be folded downwardly so that radius 2410 engages with recess 2412. Flap 2402 includes a hinge 2416 that can be folded along a hinge line through an arc. Radius 2410 and recess 2412 “mate” and can be arranged so that they “snap” into a matingly engaged position, thereby holding the flap 2402 firmly in position against the tray 2400.

[0658] Referring now to a cross-sectional view of the stacked trays in FIG. 90, an alternate embodiment of tray 2400 is shown. This embodiment is substantially similar to the embodiment shown in FIG. 88 except that this embodiment includes lip 2428 (discussed below). In both embodiments, flap base 2418 is shaped so as to correspond with profile of flanges 2406 and 2408 and a ridge 2426 is located along the external edge of flap base 2418 such that when a finished package is stacked above another similar package they will “nest” together and the upper tray is prevented from contacting the contents of the lower tray. The base 2420 of the tray can be formed with a profile providing an upwardly extending depression that extends above the highest point of the contents in the lower tray. In this fashion, the finished packages can be stacked within cartons for distribution and shipped long distances without causing damage to contents of the trays in the lower position. The tray 2400 has recessed base 2420 to clear goods in the tray below. The lip 2428 formed by the over-wrap can be heat sealed after folding of the flap 2402 by heat seal bars 2430 to ensure that flap 2402 is retained in folded position as shown in the stacked finished packages FIG. 90. Ridges 2432 can be formed into flaps to improve rigidity and stability of the finished pack as shown in FIG. 89.

[0659] 3.2.24 Embodiment

[0660] Another aspect of the invention is shown in FIG. 91. FIG. 91 shows a tray 2500 prior to folding and bonding of the flaps. FIG. 92 shows a view of a section of the tray 2500 after folding and bonding of the flaps to the tray wall. In this aspect, sections may be added to the edges of the flaps that are not connected to the tray 2500. Because such sections can be added to many embodiments of a tray with flaps, further features of the tray and flaps will not be discussed in detail, however several detailed embodiments with flaps including these sections are discussed later in this application.

[0661] The tray section shown in FIGS. 91-92 details a single corner section of a four cornered tray, however, all four corners of the tray with flaps can be similar. Flaps 2504 and 2502 are shown attached to a tray 2500 at a hinge 2516. The flaps 2504 and 2502 can be printed by ink jet devices, prior to folding and bonding. Adhesives can also be applied by ink jet printers to the flaps and tray. Hinge lines 2576 and cut lines 2578 are provided around the periphery of the flaps 2502 and 2504. The cut lines 2578 and hinge line 2576 terminate at points 2580 and 2582. Hinge line 2576 provides a means to fold sections 2586 at the bottom of flaps 2504 and 2502, which can be folded and bonded to the base of tray. However, it is apparent that hinge line 2576 and cut line 2578 need not run continuously around the periphery of the flaps 2502 and 2504. Hinge line 2576 and cut line 2578 could be cut into the shorter sides of the flaps 2502 and 2504 from the points 2580 and 2582 to the free corner of the flaps. The area between the cut line 2578 and the hinge line 2576 on flaps 2502 and 2504 form walls 2594 and 2592 respectively.

[0662] According to the present invention, a method for production of trays with flaps includes a thermoforming process and a “cut in place” procedure. The term “cut in place” is a common term used by those skilled in the art of tooling manufacture and use of thermoforming equipment. This term describes a thermoforming production method including the use of a thermoforming tool with a cutting devices incorporated into the tool so as to permit cutting of the subject thermoformed component from a web of plastics material immediately after forming and before ejection and removal of the component(s) from the thermoforming tool.

[0663] Referring now to FIG. 93, a cross-sectional view through a corner 2572 of the tray 2500 with flaps 2502 and 2504, after the flaps have been folded and bonded, is shown. The “cut in place” forming method allows a method to provide walls 2592 and 2594, which are extensions of flaps 2502 and 2504 that can contact each other, as shown, and be bonded together after folding the flaps into the finished position. In this way, a substantially more rigid tray structure can be provided that would otherwise require a heavier wall section for trays that have not been provided with flaps as herein disclosed. With ink jet application of adhesives, as described herein, an efficient means of economically applying the minimum quantity of adhesives is provided. In this way, adhesives can be applied in a pattern that allows for maximum surface area bonding of trays and flaps while minimizing the quantity of adhesive material required.

[0664] In another preferred embodiment, adhesives such as any suitable bonding medium may be applied to surfaces of the flaps of tray and the tray walls and base by any suitable “ink jet” apparatus. Furthermore, colored graphic printing and any desired information can be printed and/or applied to any desired surfaces of the tray and flaps by any suitable “ink jet” apparatus. The “ink jet” equipment is manufactured by several companies such as Hewlett Packard, Xerox, SciTex, Marconi/Video Jet and others. The equipment can be arranged to apply inks, lacquers and adhesive materials as required by, for example, arranging the ink jet equipment adjacent to a conveyor that can transport the trays with flaps at a suitable speed and in such a manner as to allow application of the inks and other materials to the trays and flaps, as required. A conveyor may be arranged adjacent to and integrated with thermoforming machinery such that immediately after producing trays with flaps, the trays can be automatically transferred onto the conveyor. The conveyor can be arranged to carry trays with flaps at a controlled speed and as required to allow application of inks and any suitable materials thereto by ink jet printer.

[0665] 3.2.25. Embodiment

[0666] Referring now to FIGS. 94-96, another aspect of a tray with flaps constructed according to the invention is shown. This aspect includes a crest 2602 and a concave indentation 2624 in the flap base 2604. These features are provided to offer improved stackability. Because these features can be incorporated into many of the trays with flaps presented and other trays with flaps constructed in accordance with the present invention. Only these features of tray 2600 will be described in detail in this section.

[0667] Tray 2600 includes a crest 2602 (similar to crest 1350 shown in FIG. 46 of tray 1300) constructed on the perimeter of the tray opening on a wall of the tray 2600. A similar crest is also constructed on opposite sidewall so as to form two convex areas having a first radius. Referring now to FIG. 95, a flap is shown with a flap base 2604 having a concave indentation 2624 of a second radius. When folded, as in a finished package, flap base 2604 is substantially level with the tray base 2616. Two such flap bases are provided, each in opposing sides from the other. Turning now to FIG. 96, a plurality of finished stacked packages using the trays of FIG. 94 is shown. The flap base concave indentation 2624 radius is smaller than the radius of tray crest 2602, so that when stacked, flap base 2604 of upper tray 2612 makes contact with tray crest 2602 of lower tray 2614 at two locations 2608 and 2610. In this manner, trays are prevented from rocking back and forth. A space is provided between upper tray 2612 and lower tray 2614 which is also shown in FIG. 96. In this manner, the underside of tray base 2616 is prevented from touching the sealed or overwrapping web on lower tray. The sealed or overwrapped web material substantially holds the fresh meat portions to the tray base. In one instance, the web material is oxygen permeable. Finished packages can thus be stored and packaged in any of the master containers disclosed herein. The disclosed tray profile allows stacking of several layers of trays in a vertical stack, wherein each loaded and over wrapped tray is located directly above and in contact with a lower tray to maximize density of a finished master container. The profile of the flaps is an upwardly arched base that corresponds with the profile of the tray upper flange profile. In one aspect of the invention, ground meat is extruded with a profile that corresponds to the inner profile of the cross section across the length of the tray such that when loaded into the tray, the upper surface of the extruded grinds portion is in firm contact with the tray over wrap so that it holds it in place and slightly below the upper edge of the flanges. The end flanges are arched to match the arched base and end flap profile of the lower tray profile. Continuous bonding of each flap around its perimeter to ensure that the end edge butts up and contacts the adjacent flaps provides for maximum structural stability and minimum twist after fabrication and bonding. Thus, the double walls (inner cavity and outer flap) improve crush resistance.

[0668] 3.2.26. Embodiment

[0669] Referring now to FIG. 97, an embodiment of a pre-form tray web with flaps is illustrated. The pre-form tray web 2700 can be shaped into a finished tray. The web can be constructed of any suitable material such as PVC, PP or other suitable materials herein disclosed in this specification. The method used to form the web can be thermoforming or any other suitable methods. The web 2700 is constructed of a rectangular base 2702. The base is surrounded by four upwardly extending walls 2704, 2706, 2708 and 2710. The walls may be outwardly reclined to facilitate the removal of the web from a mold or the nesting together in a stack of similar tray pre-forms (not shown).

[0670] The walls are connected to the base 2702 at a lower portion thereof and adjoining walls are connected to each other thusly forming corner sections. In this embodiment, the corner sections are made from the ends of the walls being creased inwardly 2714 where the ends attach to an adjacent wall. Thus, two ends of two walls form an inwardly extending corrugation 2712 to give the web additional strength when finished into a tray.

[0671] Two walls 2702 and 2708 of the four walls on opposing sides are formed with an upwardly extending region 2716 in the center, and an angled shaped bottom edge 2718 to give the finished trays the ability to be stacked atop one another without allowing the sealing web of a lower tray to touch the base of the adjacent stacked upper tray. While an angled bottom has been shown, the shape may take an arcuate form. Furthermore, the base is configured to have similar angled surfaces or arcuate shape that corresponds to the shape of the lower portion of the side walls 2702 and 2708.

[0672] The upper edges of the walls 2704, 2706, 2708 and 2710 are attached to flaps 2720, 2722, 2724 and 2726, respectively. Referring now to FIG. 95, the flaps are joined to the upper edge of the walls at a hinge 2728 to allow the flaps to rotate inwardly. The finished tray 2730 will thusly include an outer 2732 and an inner 2734 reinforcing wall made from the flaps. The flaps include a tab 2736 connected to one edge of the flap which can be folded inwardly as shown in FIG. 98 to press fit into a groove 2738 formed at the lower perimeter of the base 2702. The member formed by the folded tab 2736 thus forms a securing device which is press fitted into the corresponding base groove 2738 without the need for bonding the flaps to the finished tray with adhesives thereto.

[0673] 3.2.27. Embodiment

[0674] Referring now to FIG. 99, an alternate embodiment of a pre-form tray web with flaps is illustrated. The pre-form web can be either thermoformed or injection molded from any suitable plastics material, such as polypropylene. The web 2800 includes a base 2802 with four vertical walls 2804, 2806, 2808 and 2810 connected to the base 2802 at lower edges of the walls thereof. The pre-form tray web 2800 is in one instance constructed by injection molding or other suitable method, such as thermoforming. The walls may be inclined to facilitate the removal of the web pre-form from a mold. The base is connected to the walls at lower portions thereof, and the walls are connected to each other at adjacent ends, thusly forming corners 2812, 2814, 2816 and 2818 where the ends of walls connected to each other and to the base 2802 meet. Opposing two walls 2810 and 2814 of the four walls are formed with angled edges at a lower central portion thereof to form a recess under the base of the tray so that upon stacking of finished trays, the goods are not in contact with a lower stacked tray. The base 2802 is likewise configured with angled surfaces to correlate to the shape of the walls 2810 and 2814 so that the base 2802 is aptly suited to minimize contact with the goods of a lower stacked tray.

[0675] The upper edges of the walls include flaps 2820, 2822, 2824 and 2826 suitably constructed so as to inwardly rotate about a hinge around the perimeter of the opening. Referring to FIG. 100, the flaps are constructed with a number of surfaces 2828 and 2830 at desirable oblique or perpendicular angles to impart strength to the flaps and the finished tray in the form of a structural member. FIG. 99 illustrates one embodiment of surfaces 2828 and 2830. In FIG. 99, surfaces 2828 and 2830 form oblique or perpendicular angles that extend upward from the top of the tray when the flaps are folded inward and downward: FIGS. 100 and 101 illustrate an embodiment in which the surfaces 2828 and 2830 form an oblique or perpendicular angle that extends downward toward the base 2802 of the tray when the flaps are folded inwardly. The embodiment illustrated in FIGS. 100 and 101 also includes a flange 2834. The flaps may partially rest upon the flange 2834 when folded inwardly to increase the strength and stability of the flaps in the downward position. As with other trays disclosed herein, the trays of this embodiment are intended to be stackable atop one another. Referring now to FIG. 101, a portion of a finished tray with goods 2832 placed therein and folded flap 2836 is illustrated.

[0676] 3.2.28. Embodiment

[0677] Referring now to FIG. 102, another alternate embodiment of a pre-form web for finishing into a tray is illustrated. The web in this embodiment can be thermoformed of suitable materials disclosed herein or by other suitable methods known in the arts. The web 2900 includes a rectangular base 2902 with four walls 2904, 2906, 2908 and 2910 attached at the respective four sides around the perimeter of the base 2902. The walls contain ribs 2922 to add structural rigidity and strength to a finished web. When the flaps are folded, the flaps can be bonded to the ribs, which project outward, thusly allowing bonding of the ribs to the flaps. In this manner, the flap faces 2924 can be pre-printed with a barcode containing relevant information or other product description.

[0678] The walls are connected to each other at adjacent ends thereof, respectively. The four adjacent walls are joined to each other by corrugated sections 2912, 2914, 2916 and 2918 joining a first end of a first wall to a second end of a second wall and so on. When the web 2900 is finished into a tray, the corrugated sections will appear as shown in FIG. 103. The corrugated sections are intended to impart rigidity and strength to the finished tray 2920. For example, under certain thermoforming or injection molding conditions, the lower corners where the base and walls are connected, the web material may be stretched or “thinned” out, thus creating a weak spot and a potential source for leaks. By forming a web with corrugated corners the weak sections of the finished tray are strengthened accordingly.

[0679] 3.2.29. Embodiment

[0680] In another alternate embodiment illustrated in FIG. 104, a tray is constructed with flaps having contoured ends to substantially lie adjacent to a corner where the base and walls are joined together, when the flaps are thusly folded. The flap ends may reinforce the corners of the finished tray by overlapping and/or wrapping around the corner sections on the bottom and sides thereof. One or two flap ends may be bonded to a corner to reinforce the corners. In one actual embodiment, a tray 3000 includes four flaps. Flaps 3002 and 3004 include contoured end portions 3006 and 3008, respectively, rounded to conform to a rounded corner 3010 of the web base and walls. A first flap 3002 is folded and bonded to the tray 3000 such that the rounded end portion 3006 of the flap 3002 overlaps the corner area 3010. A second flap 3004 has an end portion 3008 can be folded on top of the first rounded flap end portion 3006 to doubly strengthen the corner section 3010 of tray 3000, as illustrated in FIG. 105.

[0681] 3.2.30. Embodiment

[0682] Referring now to FIG. 106, a tray is shown in a three dimensional disposition. The tray 3100 is arranged with a base 3140 and four upwardly extending walls terminating at a flange 3142. The four walls and the base define a cavity 3144. Attached to the flange 3142 are four flaps 3132, 3134, 3136 and 3138. In FIG. 106, all four flaps are folded outwardly and downwardly along a hinge that connects each flap to the tray. Each of the walls may be rigidly fabricated by bonding together, two or more layers of the tray material. Several embodiments disclosed provide increased rigidity to the side walls of the finished tray by bonding flaps to the tray walls. The current embodiment offers a means to increase the number of layers of material bonded to the tray walls. In this way, the tray walls can be rigidly constructed with higher compression resistance and at a lower cost than would otherwise be incurred for a single or double layer finished wall of a similar compression resistant rigidity.

[0683] FIG. 108 shows tray 3100 with its flaps unfolded, so that the layers of material that will form the finished side walls can be illustrated in detail. Referring now to FIG. 108, a thermoformed pre-form is shown which can be manufactured from any suitable material, of any suitable thickness. In one instance, preforms are thermoformed from extruded polypropylene sheet with a thickness of approximately 0.018″. The polypropylene sheet is then thermoformed to produce a pre-form, which is constructed so that it can then be folded and bonded into a stackable tray profile. The pre-form consists of a cavity 3144, with a series of semi-rigid flaps, all connected by at least a single hinge to the flange 3142. Cavity 3144 has a base 3140 with four upwardly extending walls terminating at a continuous flange 3142. Flange 3142 may be arranged with four straight sections connected via rounded corners but the other packaging tray configurations may be fabricated of any suitable configuration. At the outer perimeter of flange 3142, adjacent flange flaps 3136, 3174, 3198 and 3182 are attached via hinges shown as 3118, 3120, 3122 and 3116, respectively.

[0684] Located at each corner of the tray 3100 between each adjacent pair of flaps, corrugated flaps are provided. Between adjacent flange flaps 3136 and 3174 a pair of generally corrugated adjacent flaps 3152 and 3164 are located. Corrugated flap 3152 is attached to flap 3136 by hinge 3126. Corrugated flap 3164 is attached to flap 3174 at hinge 3168. However, corrugated flaps 3152 and 3164 are severed completely from direct attachment together by cut 3128. Similarly, corrugated flap 3176 is attached to flap 3174 via hinge 3170 and corrugated flap 3180 is attached to flap 3182 via hinge 3192. Additionally, corrugated flap 3181 is attached to flap 3182 via hinge 3184 and corrugated flap 3190 is attached to flap 3198 via hinge 3196. Finally, corrugated flap 3106 is attached to flap 3136 via hinge 3104 and corrugated flap 3110 is attached to flap 3136 via hinge 3124. The pair of corrugated flaps 3110 and 3106 are severed along cut 3108, the pair of corrugated flaps 3152 and 3164 are severed along cut 3128, the pair of corrugated flaps 3176 and 3180 are severed along a cut 3178 and the pair of flaps 3181 and 3190 are severed along cut 3188. Each of the corrugated flaps may be folded along the hinge connecting it to the flap in a downward direction. When the flaps are folded downward and outward, the corrugated flaps will be positioned between the flaps and the tray walls as can be viewed in FIG. 107. The corrugated flaps may then be bonded to the flap at the points of contact between the corrugated flap and the flap. The corrugated flaps may also be bonded to the tray wall at points of contact between the tray wall and the corrugated flap. In this manner, the finished side walls of the tray will be composed of three layers in certain locations increasing the rigidity of the finished tray's side walls.

[0685] Referring now to FIG. 107, a finished side wall of packaging tray shown in FIGS. 106 and 108 is detailed. The folded can be bonded, by any suitable bonding means, at contact points such as 3162, 3158, 3156, 3154 and 3150. Bonding can be arranged to follow a path near the perimeter of each flap so as to hermetically seal space 3148 therein.

[0686] Referring now to FIG. 109, a cross section through flange 3142, cavity wall 3160 and flap 3136 details an embodiment wherein hinge 3118 is located parallel to a second hinge 3130 with flap section 3131 between hinges 3118 and 3130. Flap 3136 is then bonded to wall 3160 at 3133.

[0687] Referring again to FIG. 108, in an alternate embodiment, flap 3172 may be provided that is attached to the peripheral edge of flaps located at opposite sides of the tray 3100. These flaps 3172 are attached to the flaps via hinges 3166. Flaps 3172 may also be similarly attached via hinges to all flaps, if so desired. In this embodiment, pairs of corrugated flaps 3176 and 3180, 3164 and 3152, 6610 and 6606, 3180 and 3190 can be deleted and flaps 3172 folded downward against what will become internal surfaces of flaps. When the flaps are folded outward and downward, the flaps 3172 will be positioned between the flaps and the tray walls 3160. In this manner, a three layer finished side wall may be constructed similarly to the structure shown in FIG. 104. It may be desirable to corrugate flaps 3172.

[0688] 3.2.31. Embodiment

[0689] Referring now to FIG. 110, another embodiment of a pre-form tray 3200 is shown, wherein a centrally located cavity 3204 is connected via hinges 3216, 3208, 3220 and 3218, to flaps 3202, 3206, 3210 and 3214 respectively. Additional flaps 3212 and 3222 are attached via hinges to flaps 3202 and 3210. Ribs, such as the ribs shown in the additional flaps 3212 and 3222, can be provided to all parts of the tray cavity, walls, and flaps. Furthermore the ribs can be arranged in any suitable profile so as to maximize rigidity of the finished tray. Ribs and ridges may be positioned in any direction, including either vertically or horizontally along the surface of the tray and flaps to resist crushing and torsion of the finished tray during manufacture, handling, and transport. In FIG. 110, ribs are shown only in flaps 3212 and 3222. Referring to FIG. 111, one embodiment of ribs 3252 are shown. FIG. 111 is a cross-sectional view of flap 3222 along line 3230. The profile of the ribs is generally tapered with the widest portion of the tape coupled to the flap 3222. Furthermore, the ribs nearer the edge of the flap 3222 opposite the flap 3202 may project further from the surface of the flap 3222.

[0690] Referring now to FIG. 112, two pre-forms 3224 and 3226, similar to the pre-form shown in FIG. 110 are shown stacked and nested together. In this way, pre-forms can be manufactured and conveniently stacked in a nesting configuration, minimizing the volume of space required during storage and shipping thereof. In this manner, pre-forms may be fabricated at the point of use for packaging goods.

[0691] 3.2.32. Embodiment

[0692] Referring now to FIG. 113 and FIG. 114, another packaging tray 3300 is shown with a cross sectional view shown in FIG. 114 therethrough. Tray 3300 may be manufactured from any suitable material, such as but not limited to polyethylene. A cavity 3318 is surrounded by upwardly extended composite side walls 3312, 3306, 3302 and 3304 all terminating at flange 3320. Composite side walls 3306 and 3312 are visible and ribs 3310 and 3308 are shown in composite side wall 3306 and ribs 3316 and 3314 are shown in composite side wall 3312. Composite side walls 3312, 3306, 3302, and 3304 are formed by folding flaps attached to the flange 3320 in an outward and downward direction. The folded flaps are then hermetically bonded to the side walls of tray 3300. The internal structure of a portion of composite side wall 3306 can be viewed in FIG. 114.

[0693] Referring now to FIG. 114, a cross section through ribs 3310 and 3308 of FIG. 113 is shown. Hinges 3322 and 3324 are arranged to allow folding of flap 3307 against the tray wall 3330. Hermetic seals are shown at 3326, 3332 and 3336. Hermetic seals shown as 3326 and 3332 follow a path completely around the perimeter of rib 3310 and hermetic seals shown as 3332 and 3336 follow a path completely around the perimeter of rib 3308. In this way, spaces 3328 and 3334 can be completely enclosed and hermetically sealed separately from each other. However, prior to bonding ribs so as to enclose and hermetically seal spaces 3328 and 3334, any suitable gas such as carbon dioxide at any suitable pressure, such as a relatively high pressure, such as 80 psi, can be provided therein. In this way a rigid tray can be manufactured with reduced material content and therefore at relatively lower cost. Other spaces may also be provided with high pressure gas to add rigidity to any tray part thereof.

[0694] 3.2.33. Embodiment

[0695] Referring now to FIG. 115, a tray 3400 with lateral ribs arranged in a similar manner to those (3316, 3314, 3310 and 3308) disclosed in FIG. 113 are shown. FIG. 116 shows spaces 3416 and 3422, enclosed within the composite side wall and hermetically sealed within ribs 3418 and 3424, along seals 3414, 3420 and 3426. The spaces 3416 and 3422 can be filled with high pressure gas, such as CO₂. Hinges 3408 and 3412 are located so as to provide an outwardly extending flap that may be folded against the tray wall 3440 to form a composite wide wall. A web of material shown as lid 3442 can be hermetically sealed to flange 3406 so as to fully enclose cavity 3438. Apertures such as 3436 can be provided to allow liquids to enter cavity 3428. Seal 3432 prevents escape of such liquids from space 3428. Ribs such as 3430 can be provided.

[0696] 3.2.34 Embodiment

[0697] Referring now to FIG. 117, two thermoformed trays 3500 and 3514 are shown in a partially nesting disposition. The profile of tray 3500 is arranged with upwardly extending walls terminating at flange 3502 with inwardly extending ribs 3506, formed into the walls. Ribs 3506 formed in tray 3500 extend inward toward the center of cavity 3504 and ribs 3510 of tray 3514 extend outwardly away from a centrally disposed cavity.

[0698] Referring now to FIG. 118, the two trays 3500 and 3514 in FIG. 117 are shown sealed together to form a single tray 3518. Flanges 3502 and 3516 are hermetically sealed together around the full length of what has become a path close to the tray perimeter. FIGS. 119-120 show details of enclosed spaces such as 3526 and 3528 that are formed when trays 3500 and 3514 with ribs 3508 and 3510 are bonded together. The area of the tray surrounding the ribs is also hermetically sealed such that ribs formed in the walls of the inner tray are adjacent to the corresponding rib in the outer tray to provide fully enclosed spaces such as 3526 shown in FIG. 120, that can be filled with high pressure gas. Seal paths 3522 and 3524 are shown as examples of hermetic sealing and enclosing of spaces such as 3526. FIG. 120 shows rib 3506 hermetically sealed to rib 3510, at 3532 and 3534 enclosing space 3526.

[0699] 3.2.35 Embodiment

[0700] Referring now to FIG. 121, another embodiment of a tray with high pressure gas filled spaces is provided. FIG. 121 shows a cross section through a tray similar to tray 3500 shown in FIG. 117, wherein a tray with a base 3612, and upwardly extending walls 3616 terminating at flange 3600 is provided with an inward projecting rib 3608 formed therein. A separately formed outward projecting rib 3614 is shown adjacent to rib 3608 in a position prior to bonding and also after bonding to tray wall along seal path 3610. A hermetically sealed and enclosed space 3606 can be filled with high pressure gas, such as CO₂. In FIG. 122, a cross section through ribs 3614 and 3608 is shown with space 3606 enclosed therein.

[0701] 3.2.36. Embodiment

[0702] Referring now to FIG. 123, a thermoformed tray 3700 is shown in a three dimensional view located above a form cut blank 3714. Ribs are provided in the base 3704 and walls 3702, 3706, 3712 and 3716 in a vertically disposed arrangement. Any suitable rib configuration may be provided in the walls and base of any suitable size tray, in one instance, rigid ribs 3710, as shown in FIG. 123, are provided with the recess accessible from the outer side of each wall, with the ridge of the ribs 3710 extending inwardly. Trays 3700 and blanks 3714 can be manufactured in any required size, from any suitable material, such as from mono-layer extruded polyethylene terephthalate (PET) sheet. PET sheet may be extruded with multiple layers and both or a single outer layer may be provided with enhanced heat or RF (radio frequency (RF) or microwave) sealable properties. Enhanced RF sealability may be provided by including any suitable additive such as suitable metallic elements or compounds in the outer layers, by blending into the polymer prior to extrusion.

[0703] Referring now to FIG. 124, hinges shown at 3734, 3720, 3732 and 3726 are arranged so that flap portions 3718, 3722, 3725 and 3730 are all attached, thereby, to central rectangular portion 3724. In this way, flap portions can be folded upwardly about hinges so as to contact the walls of tray 3700. Flap and base portions of blank 3714 can then be sealed to the walls of tray 3700 so as to provide a hermetic seal around the perimeter of each rib after providing gas such as CO₂ at an elevated pressure in the recess of each rib. In this way a rigid tray can be manufactured with substantially less material content than would otherwise be required for a tray manufactured from a single component.

[0704] 3.2.37 Embodiment

[0705] Referring now to FIGS. 125 and 126, a side view and end view of two finished packaging trays 3828 and 3830 stacked together are shown. These figures illustrate an interlocking mechanism that can be incorporated into many of the trays disclosed herein. The trays 3828 and 3830 can be made from a thermoformed pre-form, such as the one illustrated in FIG. 110.

[0706] Upwardly extending ribs 3824 and 3826 are located on the upper surface of the flange on. The ribs 3824 and 3826 are of the appropriate size and shape to mate with recesses in the underside of a tray stacked on top and interlock with the base of the upper tray stacked on top. As can best be viewed in FIG. 126, the ribs 3824 and 3826 may be curved to increase the clearance between the upper and lower trays in the central portion of the tray.

[0707] 3.2.38 Embodiment

[0708] Referring now to FIG. 127, a three dimensional view of a corner section, of another embodiment of a stackable tray pre-form is shown prior to folding and bonding of flaps. Tray 3900 as any other tray in this disclosure, may be thermoformed from any suitable material, such as extruded polypropylene (co-polymer) sheet. Flaps 3910 and 3911 are attached at hinges 3919 and 3920 to the walls 3914 of tray. While only two flaps are shown, it is apparent that a flap that is a mirror image of 3910 is located along the tray wall opposite the tray wall to which flap 3910 is attached. Likewise, a flap that is a mirror image of flap 3911 may be attached to the opposite wall of the tray from flap 3911. While the term mirror image has been used to describe the flaps not shown in FIG. 127 it is apparent that any lettering or text applied to one or more flaps may not appear on the flap that is its mirror image. The tray with flaps can be either thermoformed or injection molded or produced in any suitable manner from any suitable material such as polypropylene, polystyrene or even emulsified fibrous paper molded in a suitable mold. Tray has a base 3917 and vertically disposed walls that terminate at a continuous flange 3918 and 3916. The surface of flange (3916 and 3918) may slope downward from the top edge of the tray walls to the periphery of the flange. The width of the flange 3916 and 3918 from the top edge of the tray walls to the peripheral edge of the flange is sufficiently wide to receive adhesive applied to the flange. To this end, in one embodiment, the width of the flange is no less than 1 mm, and sometimes no less than 4 mm. Flap 3911 may include profiled sections 3913 and 3915 that contact the vertically disposed walls 3914 of tray and can be bonded there together after flap is folded into the desired position.

[0709] Letters, such as an “S” 3912, can be formed into the flaps. These letters may comprise a word such as “TESCO” or “KROGER” or any conveniently lettered word which may be the name of a supermarket chain, or the name of a supplier of product to a supermarket and thus used as a helpful means of informing the consumer and advertising the name of the respective supermarket or supplier. Trademarks may also be formed into the flaps and arranged in any desirable way such that, for example, a trade mark, such as SAFEFRESH™, used to identify a process, product or additive used in association with manufacture of a complete retail package can be formed into the one or more end flap of the tray. In this manner, the letters or trademarks formed into flaps can be formed such that the base 3921 of the depression forming the letters is profiled so as to contact the vertically disposed walls of the tray after folding. A suitable adhesive or bonding agent may be applied between the base 3921 of the letters and the surface of vertically disposed walls such that the base and surfaces can become securely bonded together. In this way, a relatively rigid tray and flap structure can be manufactured that uses the formed letters as a structural component that offers a mechanical advantage and at the same time provides a low cost informing and advertising method. It is readily apparent that any lettering can be provided as a printed emblem on the outer wall of tray.

[0710] Flaps, such as 3910 and 3911, can be bonded to vertically disposed tray walls with any suitable bonding agent or process. Preferably, the bonding agent is hot water soluble or a microwave softening “hot melt” adhesive. Such a bonding process would allow for the release of the flaps 3910 and 3911, by the consumer or commercial customer after use and thereby allow flaps to return to the original formed position prior to folding and bonding. This would therefore allow stacking and easy shipping of empty trays back to the packer or packaging manufacturer, for re-use with non-food items and even with food items after adequate sanitation. Trays manufactured in the manner described in association with FIG. 127 and others herein disclosed, can be used by any person as a storage tray. The stacking feature provided in trays can provide a convenient way for a consumer to store suitable items such as nails or screws.

[0711] Recesses or dimples 3950 may be formed in base 3917 to retain and inhibit the movement of liquids such as water, blood, and purge within the tray cavity. In one aspect, the dimples 3950 are shaped and sized to maximize the adhesion forces between the liquid and the inside surface of the dimples 3950. To this end, dimples are concavely formed with a radius that may be experimentally determined to adequately utilize surface tension to retain liquids therein. Furthermore, one aspect of the invention includes shaping and sizing the dimples 3950 so that the surface tension forces at the surface of the liquid contained within a dimple 3950 are sufficient to retain the liquid within the dimple 3950. Without being bound by theory, surface tension forms only at the surface of a liquid and therefore it is desirable to have the surface of the liquid occur at the upper perimeter of the dimple (so that the maximum amount of liquid is retained within a dimple and the amount of liquid retained is controlled by the volume of the dimple) it is apparent to vary the number of dimples present based upon the moisture content of the product placed within the tray cavity.

[0712] If more dimples 3950 are needed than can be accommodated by a substantially flat and planar base 3917, the base may be profiled so that tiers, corrugations or other surface features are added to create additional surface area into which dimples may be formed. In addition, dimples may be formed on side walls.

[0713] Retention of liquids within the tray cavity by dimples 3950 inhibits the movement of liquids such as purge within the tray cavity, thus presenting a more appealing package to consumers, in addition to causing less of a mess, and increasing the yield.

[0714] Trays could be color coded to allow a consumer to decide whether or not they wanted to use the tray as a home storage tray, in which case a non-water soluble, dishwasher and microwave proof bonding agent would be used or, if the consumer intended to re-cycle the tray back into the industry distribution system, a water soluble bonding means could be indicated by a recognizable color code. In this way, a consumer could be clearly shown if the bonding agent, used to bond flaps in a complete tray and package with goods therein, was water soluble or not, prior to purchase of the tray with goods therein at a supermarket. A consumer could therefore select a package according to the type of bonding agent. If the consumer decided that a storage tray was needed to store any suitable item at home, then a tray, color-coded so as to indicate a non-soluble and dishwasher proof bonding agent could be selected at the supermarket. Alternatively, if the consumer decided that the tray should be recycled after removal of the goods contained therein at home, a tray color coded to indicate that a water soluble bonding agent, that would dissolve in a typical household dishwasher cycle, could be selected.

[0715] Referring now to FIG. 128, a cross section through a wall of an alternate embodiment of a stackable tray constructed in accordance with the method described above in association with FIG. 127 is shown. A tray cavity 3903 is contained with vertically disposed walls 3914′ that terminates at flange 3918′, and a base 3917′. A flap 3910′ is shown in folded and bonded position with bonding agents provided at contact points 3921′ and 3925. A recess 3923, which may be provided by the recess of a letter formed into the flap has a base at 3921′. A vertically disposed outer section 3927 has an upper edge 3928 terminating at flange 3918′. The lower edge of section 3927 terminates at a hinge 3929. The distance between upper edge 3928 and hinge 3929 may be pre-selected. Flap 3910′ has a vertical height 3931. The sum of the distance shown as 3927 and distance 3931 is approximately equal to the overall finished tray height, however when distance 3927 is increased and 3931 is decreased the plan area of flap shown in FIG. 127 is also decreased. In this way, the amount of material required to form a tray pre-form such as tray pre-form shown in FIG. 128 can be adjusted. For example, if distance 3927 is decreased, the area of flap 3910′ is increased and conversely, if distance 3927 is increased the area of flap 3910′ is decreased. Since the amount of flap 3910′ contributes to the rigidity of the overall tray, adjusting the length is a compromise between tray rigidity and the amount of material used. Therefore, the amount of material used can be optimized for the particular application.

[0716] 3.2.39 Embodiment

[0717] Referring now to FIG. 129 a stack of four trays constructed in accordance with the present invention is shown. While a stack of four is depicted it is apparent that the trays may be stacked in different heights such as two, three, five, six, etc. FIG. 131 shows a set of three tray stacks arranged in close proximity with one another. Trays with substantially flat vertically disposed walls have stand alone capability, meaning that they are stackable to these heights without any inter-layer sheets or columns in between. In one instance, three stacks of four trays are arranged so that adjacent stacks contact one another along their lengths. In this manner, automated means can be used to transfer using a compressive grip device in groups of twelve packages in a consistent and reliable manner. A cover 4030 is placed on top of the stacks of trays. Cover 4030 may be thermoformed to suitably mate with the tray features. The cover 4030 is designed to facilitate stacking another group of tray stacks upon the tray stacks shown in FIG. 131. The profile of the cover may be appropriately ribbed and recessed to mate snugly with the underside of the stack above it. In other aspects, the cover can be included between pouches, so that the cover is profiled to mate with the stack above and the stack below. Alternatively, the cover can be included in the interior bottom of the pouch to achieve a similar purpose for ready stacking of one pouch atop another. To this end, cover can be formed to have the negative aspect of features to mate both with stacks above and stacks below.

[0718] It may be desirable to seal the tray stacks 4010 within a pouch 4040. One non-limiting method of sealing the stacks of trays 4010 within a pouch 4040 includes placing the tray stacks 4010 within a pouch and positioning the opening of the pouch 4040 at the top of the tray stacks 4010. In this manner, the trays may be placed into the pouch 4040 from above and positioned in the bottom of the pouch 4040. The pouch may then be sealed closed to prevent outside gases from entering the pouch through the same opening in which trays entered the pouch. In the preferred embodiment, the lid is hermetically sealed to the pouch. Furthermore, a slight vacuum may be applied before sealing. Returning to FIG. 130, the pouch may be sealed to a lid 4020 that is placed on top of the cover 4030. The lid 4020 may include a flange 4002 along its perimeter to which the edges of the opening in the pouch may be sealed to create an air tight seal. The lid may be suitably thin or malleable to readily conform to the surface profile of the cover 4030. In one aspect, pouch 4040 with trays may be enclosed in a vacuum chamber, and a vacuum applied thereto, and in such a manner to cause the pouch 4040 to conform to the profile of the trays. In this manner, also, the lid will conform to the profile of the trays, thus holding pouch and lid firmly against the trays.

[0719] Said pouch 4040 may be thermoformed from any suitable materials such as coextruded or laminated Nylon//EVOH//PE. (ethyl vinyl alcohol co-polymer) A partial vacuum can be applied prior to sealing lid 4020 to pouch 4040 at flange 4002 and in such a manner so as to cause the pouch and lid to be held firmly against the outer profile of the stacks of trays 4010. Heat sealing is one suitable method of sealing the pouch to the flange 4002 although any other method of sealing known in the art and disclosed herein may be applied.

[0720] Cover 4030 may be manufactured from any suitable material such as by injection molding or thermoforming. The cover 4030 may have an upper and lower profile and will fit neatly inside the pouch 4030 and above the stacked trays as shown in FIG. 131 and cross section in FIG. 130. The edge 4004 is cleanly cut so as to not present sharp edges that could otherwise cut pouch 4040. Furthermore, the side flaps of each tray may be arranged to extend outward and beyond the edge 4004 of the cover 4030 thereby minimizing the contact of the pouch 4040 with the edge 4004.

[0721] One aspect of the cover 4040 is to provide a platform upon which the lid 4020 may rest and in to which package/trays inside pouch may nest. A soluble peelable adhesive, such as rubber cement, can be sprayed onto the cover 4030 so that it will “stick” to the base of the pouch on the outside. In one aspect, the trays may be made from recycled packages and are returnable to the sales outlet for any further use after washing/sanitizing.

[0722] One aspect of the arrangement is to eliminate the need for a cardboard carton and any other crate or carrying fixture that may otherwise be required to ship the finished retail packages from the point of packing the goods 4005 into the trays to the point of sale, such as at a supermarket. It should be noted that the column crush resistance of the trays, when stacked and as shown in FIG. 129, with bonded flaps, is substantial and when several stacks are stacked together, as shown in FIG. 131, the combined crush resistance is enhanced.

[0723] Referring again to FIGS. 129-131, various views of stacked trays that have been loaded with goods 4005, and then individually over wrapped, are shown. Referring specifically to FIG. 129, four trays are stacked vertically in a group. Referring to FIG. 131, three stacks of four trays are arranged together in a grouping of twelve trays, and a pre formed cover 4030, is located across the entire upper surface of the three adjacently stacked trays. Each individual tray has vertically disposed outer walls that contact the corresponding vertically disposed walls of trays, that are stacked directly there together. In this way, a grouping of trays as shown in FIG. 131, can be clamped together and lifted in a single unit, with just two suitably arranged vertical clamping plates, that are arranged to contact two opposing vertical faces of the stacked group of trays, and by applying compressive pressure between the two vertically arranged clamping plates, the group of twelve trays can be lifted as a single unit and loaded into a pouch, that is only slightly bigger than the overall dimensions of the clamped group of trays, together with vertically disposed clamping plates, and cover 4030. Referring now to FIG. 130, a vertical cross section through four trays is shown. The cross section shows four loaded trays with goods 4005, and where each tray has been individually over wrapped prior to stacking, within a pouch 4040. A lid 4020, is sealed to pouch 4040, at flange 4002, with cover 4030 beneath lid 4020. Prior to sealing lid 4020, at flange 4002, a partial vacuum is applied to the interior of pouch 4040, such that after sealing at flange 4002, the pouch and lid are forced by normal atmospheric pressure in such a manner that causes the pouch 4040 and lid 4020 to be held firmly against the exterior contours of the stacked trays contained therein, with cover 4030 in position. In this way, a stacked group of trays such as shown in FIG. 131, is held firmly together in a “stackable block”. An additional cover similar to 4030 may be placed within the pouch 4040 and on the underside of the stacks of trays 4010. However, this may not be necessary. In this way, the finished “blocks” of trays held within the pouch and lid can be stacked onto any suitable grocery pallet without the need of a cardboard carton. In this way, the quantity of packaging materials required is reduced.

[0724] 3.2.40. Embodiment

[0725] Referring now to FIG. 132, a stack of three trays 4102 with clear lids 4101 are shown in a side elevation. Trays 4102 are re-usable at home to store suitably sized items such as nails and screws. The clear lids 4101 are made for use in any suitable application which includes home use for storing any suitable items. The lids 4101 are profiled so as to allow stable stacking while allowing the contents of each tray to be viewed without the need to de-stack the stacked trays. The construction of each lid 4101 is substantial enough to allow use in this manner and can be made available as a purchased item at a supermarket, for example where the trays 4102 are sold with goods therein. Alternatively, the clear lids may be used as “give away” items to customers who purchase the trays with food therein and as a promotional item.

[0726] 3.2.41. Embodiment

[0727] Referring now to FIGS. 133-135, a tray with elongated flaps extending past the edge of the tray base and method of bonding flaps to trays is illustrated. In this manner, wiping of the adhesive bead during folding of flaps is avoided.

[0728] Tray 4200 includes flaps 4200 and 4203 connectable to tray 4200 at hinges 4217 and 4218, respectively. Tray 4200 also includes a flange 4201 which forms the outer periphery of tray cavity 4216. It should be readily apparent that tray 4200 is in an inverted position, such that the opening to the cavity 4216 is shown in a lower position. It should also be apparent that the tray 4200 may have as many as four flaps, one for each side of the tray. Tray 4200 also includes a tray base 4230, which in the FIG. 133 is presently located in an upper orientation. Tray cavity 4216 is formed by sides 4206 and base 4230 of the tray 4200. The tray 4200 of FIG. 133 is shown in a pre-formed stage, meaning that the tray does not have a double or composite wall construction at this stage. During this stage any suitable adhesive, such as a hot melt adhesive, may be deposited by any suitable applicator on the tray base 4230 exterior around the periphery to form beads 4208 and 4209. It should be apparent that the adhesive bead may be formed around the entire lower periphery of tray base exterior; however, for ease of illustration of the present invention, only a cross-sectional view is provided. Tray flaps 4202 and 4203 include a flap base 4204, 4205 constructed on the respective ends of flaps 4202 and 4203. Flap bases 4204, 4205 are suitably constructed to be inwardly aligned so as to provide a bonding surface on the inside regions. At a stage in the tray construction, the flaps 4202, 4203 are suitably folded at the hinge 4217 and 4218 as illustrated in FIG. 134. Flap bases 4204 and 4205 now come to rest at a location which is spaced from the adhesive bead 4208 and 4209, and do not contact adhesive beads 4208 and 4209 during the flap-folding stage so as not wipe adhesive off or otherwise interfere with the bonding during the flap-folding stage. This is brought about by constructing flaps that are of a suitable length so that the flap bases 4204 and 4205 are slightly beyond the tray base. At another stage in the process, a downward pressure is brought in the direction of arrows 4212 and 4213 to press flaps 4204 and 4205 against adhesive beads 4208 and 4209. The adhesive can be allowed to cure to produce the tray of FIG. 135 having a seal 4215 and 4214 formed therein between the flap bases 4204, 4205 and the tray 4200.

[0729] 3.2.42. Embodiment

[0730] One aspect of the invention provides a clean cut edge for thermoformed trays made from, in one instance, extruded polypropylene (copolymer) sheet, with reduced exposed sharp edges and tray corners.

[0731] One aspect of the invention is to seal, or otherwise conceal any openings at the intersections of tray members, such openings create an unappealing appearance to the finished tray because the trays look awkward and malformed. The openings, are in part, created when folding the flaps against the tray walls, particularly occurring at the upper corner of the tray where the tray and two adjacent flaps meet. It is desirable to cut trays in one plane, however, in the past, it has been particularly difficult to cut thermoformed trays at the tray corners to avoid having open spaces at the juncture of flaps and the tray flange. The present invention, therefore, provides a manner in which to close off any openings at the tray corners. In addition, the present invention requires no further equipment than that already described herein, and in the process facilitates the cutting of trays. The problem with the prior art is that there is no simple way to form a tray with flaps, wherein the tray corners are adequately covered by material. One aspect of the present invention is therefore to provide methods to close off any openings at the tray corners.

[0732] Referring now to FIG. 372, a thermoformed tray is shown after having been cut according to the present invention to facilitate the closing off of any open spaces occurring at the tray corners between two flaps and the flap flange. Previously, it has been considered difficult to trim flap ends 18600 and 18602, such that flap ends 18600 and 18602 can adequately wrap around tray corner 18604 in a manner that sufficiently closes off all areas of the tray corner, such that few open areas are detectable. The present invention provides a solution to this problem by providing a method of trimming excess material in the region of the tray corner so as to leave excess material in the form of a corner tab to adequately close off any openings.

[0733] A tray 18606 includes a first flap 18608 and a second flap 104 connected to the tray 18606 at a hinge 18612. Hinge 18612 is a horizontally disposed member surrounding the periphery of the opening of the tray 18606. Flap 18608 is attached to tray 18606 via hinge 18612, and flap 18610 is attached to tray 18606, likewise, via hinge 18612. Flap 18608 and flap 18610 are at right angles to one another, and flap 18608 and 18610 must fold downwardly so as to bond with the tray wall 18604. Flap 18608 includes a flap end 18600, and flap 18610 includes a flap end 116. Flap ends 18600 and 18602 must fit snugly at the tray corner 18604 to present an appealing package to consumers. The present invention provides a simplified method to cover the tray corner with adequate material using a corner tab 18614, which is integral with the tray hinge 18612.

[0734] As is readily apparent to one of skill in the art, thermoformed trays can be built with any amount of excess material that may later be trimmed as desired. In this instance, a corner tab 18614 extending outward from flange 18612 at tray corner is allowed to remain from the excess material left in the areas of the tray corners and adjacent flaps 18608 and 18610. A narrow slot 18616 is provided between the corner tab 18614 and the flap end 18602. A narrow slot 18618 is provided between the corner tab 18614 and the flap end 18600. Flap ends 18600 and 18602 are larger radiused at the upper portion in the vicinity of slots 18616 and 18618. In this manner, as is shown in FIG. 373, corner tab 18614 is folded downwardly to lie adjacent to the tray wall corner. Flap 18610 is folded over to lie adjacent to the tray wall, such that flap end 18602 wraps around tray corner and a portion of flap end 18602 retains corner tab 18614 in position. Flap 18608 is folded downwardly to lie adjacent to the tray wall, such that flap end 18600 wraps over the exterior of flap end 18602 and corner tab 18614. Flaps 18608 and 18610 are bonded in any suitable manner herein described. Any amount of additional adhesive may be provided at any suitable location. As is apparent from FIG. 373, corner tab 18614 provides means of closing off the previously open top portion of the tray corner.

[0735] In another embodiment of the present invention a method of stretching the overwrap material over a tray corner is provided, such that the tray corner is biased downwardly to close off any opening created by the folding of adjacent flaps in the vicinity of the tray corner. To this end, the tray flange 18612 is sloped downwardly form the interior to the exterior side of the flange 18612. In one instance the width of flange is about 4 mm. Any of the overwrapping equipment herein described can suitably be adjusted to apply additional downward biasing tension in the region of the tray corner hinge. In this manner, the overwrapping material holds the tray hinge corner in a position which closes off the opening.

[0736] In another aspect of the present invention, problems are posed by adhesive applicators that only move at right angles. Therefore in one aspect of the invention, that flange at tray corner 18620 is of sufficient radius to allow complete coverage by adhesive in one direction and at its right angle direction. It is one aspect of the invention to have the adhesive on tray flange intersect at the radiused corners. To this end, the correct flange radius can be found by experimentation depending on the flange width. Thus, it is one aspect of the present invention to form adhesive beads that have no “breaks.” In this manner, a hermetic seal can be created between the tray flange and the web lidding material. In one particular aspect, flange width is less than 4 mm to provide an adequate target for adhesive application.

[0737] Referring again to FIG. 372, it is one aspect of the present invention to include inwardly angled interior tray walls to facilitate accurate loading portions, such as ground meat portions.

[0738] 3.2.43. Embodiment

[0739] A further embodiment of a tray made in accordance with the invention is shown in FIG. 374.

[0740] Tray 18700 includes a flap 18702 that is bonded to the vertically disposed tray cavity wall 18704 with any suitable adhesive. Ridges may be suitably thermoformed into the tray cavity and flap. Web material 18706 is bonded to a continuous path along the upper flange 18708 of the tray 18700 and the web material 18706 is stretched and extended downward and parallel with the vertical wall of the flap 18702, and bonded thereto, so as to provide a rigid structural element to the finished tray package. It can be seen that the side wall construction of the finished package comprises three layers, including the tray cavity wall 18704, the flap 18702 and the web material 18706, that are bonded together. This three layer construction can allow for a reduction in material content of the total tray and web material while providing the compression resistance of a two layer tray construction which would require a greater material content. In one aspect, the web can be perforated along a path close to the upper, outer package edge 18710, such that even though the web is applied in a single piece, the portion of web that is stretched and bonded to the upper flange of the tray can be removed by peeling.

[0741] 3.2.44. Embodiment

[0742] In one aspect a double walled tray can be formed by arranging the flaps to firmly contact the base of the tray at the lower corners thereof, when the flap is folded in a single movement or action. In this manner, a flap pressing step to bond the flap to the tray is avoided. However, it is preferable to have sufficient grooves to accommodate any excess glue such that it doesn't get pushed out and thereby be exposed to sight or be able to collect dust.

[0743] 3.2.45. Embodiment

[0744] Packaging including a combination of features disclosed in any of the trays above may be combined to construct a finished package. For example, a package including a tray with any of the flaps disclosed herein may be constructed to provide desired features and inserted into either a Clysar AFG shrink bag or alternatively stretch wrapped in a pPVC stretch film over wrap or shrink wrapped with printed Clysar AFG anti fog shrink film.

[0745] Still, other packaging including a combination of features disclosed above may be combined to construct a finished package. However, perforations may be provided in depressions to allow any free liquids to pass therethrough to a space between the base of tray and the outer shrink bag. Indentations may be provided in the under (or outer) surface of the tray that can allow open cells, that may be present in the EPS structure of the tray, to absorb the liquids.

[0746] Any of the foregoing trays with flaps may be used in a method to automatically or manually perform the following steps:

[0747] Providing a tray with flaps, that has been thermoformed from expanded polystyrene (EPS). The tray having dimensions that will provide for the efficient use of the internal dimensions and capacity of typical, refrigerated road and rail transport vehicles.

[0748] Trays will retain a substantially oxygen free gas within cell structure of the tray and/or exposing the tray and/or the tray material prior to and/or during thermoforming and production of the tray, to a gas that excludes oxygen and allowing the gas to exchange with any gases contained within the cells of the EPS thereby substantially displacing any atmospheric oxygen from the cells or otherwise ensuring that gases contained in the cell structure substantially excludes oxygen.

[0749] Providing perishable goods onto the base of the tray. The perishable goods having been treated and processed to enhance the keeping qualities thereof.

[0750] Over wrapping the tray with goods therein with a web of gas permeable material such as pPVC, to produce a finished package and then seal the over wrapping web of gas permeable material to portions of the tray by a heat sealer or other suitable adhesives and then perforate the over wrapping web of gas permeable material at desired locations.

[0751] Placing the finished package or a plurality of similar finished packages into a gas barrier master container.

[0752] Displacing substantially all atmospheric gas, and particularly atmospheric oxygen, from within the master container, with a suitable gas or blend of suitable gases.

[0753] Sealing a lid over the opening in the master container to form a hermetically sealed package containing the trays with perishable goods and suitable gas.

[0754] Placing the master container inside a carton such as can be manufactured from corrugated cardboard and enclosing the master container.

[0755] Locating a plurality of closed cartons onto a standard (GMA specified) pallet (Dimensions of 40″×48″) so as to maximize the efficient use of the upper surface area provided by the pallet thereby producing a loaded pallet.

[0756] Storing the loaded pallet for a period of time in refrigerated space.

[0757] Delivering the finished pallets to a point of sale such as a supermarket.

[0758] Performing all aspects of the process in temperature controlled conditions

3.3. Packaging Systems

[0759] Anyone of the aforementioned trays may be used in anyone of the packaging apparatus and packaging methods herein described below. One aspect of the invention provides an apparatus and method to produce packages that have been sealed under conditions that substantially excludes oxygen. This encompasses not only the sealing of a lidding material to a tray with beef therein, but also, the methods and apparatus used to form the tray, the lidding material, and the loading of master containers with finished packages, all produced under conditions which substantially exclude oxygen therefrom.

[0760] Without limitation, one aspect of the invention provides one or more vacuum chambers to evacuate the package before sealing or otherwise applying a lidding material to a tray.

[0761] Without limitation, one aspect of the invention provides an enclosed packaging conduit, wherein the conduit is padded with a desirable gas that substantially excludes oxygen from the packaging process. Sealing or otherwise applying a lidding material to a tray can therefore proceed under reduced oxygen conditions.

[0762] In addition, in other aspects, the invention provides ancillary apparatus for the folding and bonding of tray flaps in association with the packaging apparatus; and still further aspects of the invention provide for the introduction of substances to deplete oxygen within packages.

[0763] In still further aspects, the invention provides materials and methods for the construction of lidding materials which are included within the packaging apparatus herein described.

[0764] 3.3.1. Embodiment

[0765] A first embodiment of a packaging system is illustrated in FIG. 136. Referring now to FIG. 136, a schematic illustration of a tray sealing apparatus is shown to produce packages, including a tray, a web and perishable goods contents shown as ground meat. The perishable goods may be portions of beef, pork, or any other suitable perishable goods. A horizontally disposed, continuous conveyor 4326 including a number of carrier plates 4302 suitably attached to chains is arranged adjacent and below a series of processing stations. The conveyor 4326 is driven by a driver that intermittently indexes in a forward direction indicated by arrow 4328, at a rate of one carrier plate per indexing step. Trays 4300, stacked in a vertical disposition in a container, are dispensed into apertures in the carrier plates 4302. With each progressive forward indexing movement of the conveyor 4326, certain operations carry out functions to arrive at a packaged tray with product. Cutting devices positioned along the conveyor 4326 generally denoted by 4304 severs flaps. Product, such as portions of ground beef, are loaded into the tray at a product loading station 4306, and a web of material 4308 is heat sealed, or otherwise bonded, to a tray flange at a heat sealer station 4312. Scrap material from web 4308 is wound onto scrap roll 4310. In one instance, tray apertures are provided by heated pin devices at station 4314. Flaps are folded over by rotating about hinge so as to then locate flaps adjacent to tray 4300, at flap turning station 4316. Flaps are then sealed to tray at station 4318 and flap trimming is performed as may be required at station 4320. Labeling is done with a tray labeler at station 4322. The finished tray with perishable goods packaged therein is ejected from the conveyor at an ejector station 4324.

[0766] Referring now to FIG. 137, a tray constructed according to the present invention is shown in an inverted position. The tray 4302 includes apertures 4322 made by the apparatus of FIG. 136.

[0767] 3.3.2. Embodiment

[0768] FIG. 142 shows a packaging machine constructed according to the present invention to apply label(s) to the first web of trays sealed with at least two webs. In a further aspect of the invention, the apparatus can be used with an alternative printing device to print directly onto the web or over wrap. In some embodiments, the web printed upon will be the inner first web. Reference is also made to patent application PCT/AU93/00484, which is herein incorporated by reference. FIG. 138 shows a side elevation of the packaging apparatus and FIG. 139 shows a plan view of the upper side of the packaging machine of FIG. 138. Packaging machine 4400 is arranged in two sections to provide a space so as to allow a sufficiently clear area to install a scale 4402 with load cells 4428. In one instance, packaging machine 4400 is mounted and attached to the floor independently of scale 4402 such that they are not in contact with one another. First web unwind roll 4406 is provided with braking devices attached thereto. Drive 4404 is arranged to unwind first web from roll 4406. Printer 4408 is located between first web roll 4406 and second web roll 4410. Printer 4408 is attached to driver to move in X, Y and Z axis in horizontal and vertical planes. Printer 4408 includes a mechanism to print onto labels and then apply labels to first web or alternatively print directly onto first web Second web roll 4410 is located above first web 4412 and is fitted with braking devices as well to maintain tautness of the web as it is unrolled. Packaging apparatus 4400 includes a vacuum chamber assembly. The assembly includes a number of components including a lower 4416 and upper 4424 vacuum chamber portion, a lower 4420 and upper 4422 plate and a sealing plate 4418.

[0769] Referring again to FIG. 138, printer 4408 is equipped so as to either apply a label or print desired information onto first web 4412. Load cells 4428 are located along a beam 4454 that extends across and under the full width of sealing plates 4418. Beam 4454 can be elevated and lowered. Scale 4402 and beam 4454 is arranged to elevate load cells 4428 upwardly so as to contact underside of trays in apertures of sealing plates 4418 and lift the trays from apertures in sealing plates 4418 in conveyor. Trays are lifted to an extent that prevents any contact with anything else apart from the load cells 4428. The weight of each separate tray can thereby be determined and this information is transferred to a printer 4408. Printer 4408 prints, information onto labels (prior to application of label onto first web) or directly onto the first web 4412. First 4412 and second web 4456 are then laminated together before heat sealing to flanges of the tray web.

[0770] Referring now to FIG. 139, an upper plan view of the apparatus of FIG. 138 is shown. First 4406 and second 4410 web rolls are seen traversing approximately the entire width of apparatus 4400, so as to enable the sealing of two packages simultaneously.

[0771] FIG. 140 shows one embodiment of a single register detail that may be applied directly onto first web 4412 or to a label. The single register detail includes a frame 4442 of heat activated adhesive that can be printed directly onto web. The frame is arranged with dimensions that correspond to the tray flange of the tray web such that the frame 4442 covers the flange located above the tray web. Other details of package contents are also shown and numerous boxes 4446 provide areas onto which information can be printed at the time of packaging. Barcode 4447 contains product information, such as date of packaging and weight, which can later be used to determine price at the point of sale.

[0772] 3.3.3. Embodiment

[0773] Trays constructed according to the present invention can be sealed by one or two webs. In one aspect, the web(s) are sealed to the tray flap in the non-folded state in sealing stations. Upon bending of the flaps, the web(s) are stretched, thus, providing a taut appearance and protection for the perishable goods inside.

[0774] Referring now to FIG. 141, an apparatus for the production of packaged perishable goods is schematically illustrated. In one aspect, this embodiment can be used for the packaging of shallow products such as boneless pork loin chops, butterfly steaks, thick-cut bone in pork chops and New York Strip, super trim beef and pork cuts that are generally not displayed in the package by shingling but are laid flat and adjacent to each other and spaced apart so that a consumer can inspect carefully. However, it is apparent that the apparatus and method can also be used to package any perishable product, such as beef.

[0775] FIG. 141 shows a sketch of a side elevation of a packaging machine constructed according to the present invention that can be used to produce packages of the types described herein. The packaging machine includes a frame supporting a conveyor 4510. The conveyor is carried on a first 4544 and second 4528 roller sprockets located on opposite ends of the frame. The first roller sprocket can be fitted with a drive chain secured to a driver 4542. In this manner, by turning one roller 4544, the conveyor 4510 can be incrementally or continuously moved. Continuous conveyor 4510 carries sealing plates 4512 in the direction indicated by arrow 4526 across a plurality of processing stations. Details of a sealing plate 4512 will be described herein below. Sealing plates 4512 are attached to the conveyor 4510 via attachment points. Web unwind rolls 4530 and 4532 and scrap web wind-up arrangements 4520 and 4538 are provided to supply the apparatus with a web to seal to the trays. A first loading station, generally denoted by reference numeral 4518 provides perishable products into trays carried by the sealing plates 4512. Conveyor 4510 next carries trays with perishable products to a first sealing station having a first 4514 and second 4520 sealing assembly portions. First portion 4514 is mounted on an upper side of the conveyor 4510, and the second portion 4520 is mounted on an underside of the conveyor 4510, so as to approach the trays from opposite sides thereof. The packaging apparatus includes a heat sealing device 4516 located downstream of the vacuum chamber. Conveyor 4510 is supported within the frame and is attached to a powered indexing device for moving the conveyor 4510 and sealing plates 4512, intermittently and in a direction from loading section 4518 toward sealing station 4514. Each intermittent movement of conveyor 4510 travels one pitch which is equal to at least the distance required to move a sealing plate 4512 the full distance of the length of the sealing plate. Thereby, with each movement of the conveyor, a sealing plate with tray is located directly between the lower vacuum chamber portion 4520 and the upper vacuum chamber portion 4514. A sealing plate is also located directly beneath heat sealer 4524. This arrangement transfers a package that has been evacuated of undesirable gases in the vacuum chamber 4514 to be sealed in heat sealer 4516. The driving devices for the packaging machine, machine components and conveyor are a pneumatic cylinder and electrically powered driving motors of suitable size and capacity. As the conveyor indexes forward, the web assemblies 4530 and 4532 unwind to provide new web material to seal to tray, while web take up rolls 4520 and 4538 pick up the scrap material.

[0776] 3.3.4. Embodiment

[0777] FIG. 142 shows a schematic representation of a side elevation of a packaging apparatus including a conveyor 4670 with a plurality of sealing plates 4636 generally denoted 4636 attached thereto. A drive motor 4638 is connected to conveyor sprockets 4640 and 4641 and arranged so as to provide intermittent driving of the conveyor 4641 as required. Trays 4647 with goods therein are loaded into apertures in sealing plates at the loading section and the conveyor 4670 is driven forward in the conveyor direction shown in intermittent increments which are equal to the distance of a single sealing plate. The conveyor 4670 is otherwise stationary except during each movement of indexing. A scale 4642 can be positioned under the upper section of the conveyor and is attached to a driver such that when the conveyor is stationery the scale 4642 can be elevated and lift the tray 4647 from sealing plate 4636, and weigh the tray and goods. Presumably, the tray weight will be known, and the weight of the goods can therefore be obtained. In one instance, scale 4642 can be interfaced with a label printing device 4649. The labels may include information such as price, weight and time of packaging and then label printing device will apply the label to the upper surface of the first (or second web) in a desired label position. Label position can be predetermined such that when tray, first and second webs are sealed together, the self adhesive label is in a desired location which can be easily seen by any prospective purchaser of the finished package after removal of the second web. Alternatively, if the label is located on the second web and if the second web is not removed before retail display then the label can be viewed. A roll of material 4644 is mounted above the conveyor adjacent to a first station 4646 to facilitate unwinding of the material 4643. The material may include a single web of material or alternatively the material may include a roll of two laminated webs such as described above. Packages produced with material according to the present invention would be similar to packages shown in FIG. 143, whereas packages produced with a single web of material would resemble the package in FIG. 144.

[0778] First station 4646 includes an upper vacuum chamber 4648 and lower vacuum chamber 4650 and both are mounted to the packaging machine and attached to pneumatic drivers. Pneumatic drivers are arranged to move the upper 4648 and lower 4650 vacuum chamber in a reciprocating upward and downward motion. Vacuum chambers operate such that they move simultaneously but in opposing directions such that when they are moved toward each other a sealing plate 4636 is clamped therebetween to provide a completely enclosed chamber that is isolated from ambient atmosphere. Each vacuum chamber has ports 4652 that is attached to a vacuum pump (not shown) and sources of gases via ports 4652. The gas sources can be several in number but typically can include: substantially 100% carbon dioxide and a blend of carbon dioxide and nitrogen in any concentration. Sources of gas can be switched from one to the other such that a selected gas can be injected into the chamber as required and at will. For example after evacuation of the vacuum chambers, a gas, such as substantially 100% carbon dioxide, can be provided in the vacuum chamber at a gas pressure above ambient atmospheric pressure, for example about 25 psi. Gas pressure may, then be reduced to any pressure between about 0 and about 25 psi before providing a gas, such as substantially 100% nitrogen, in the vacuum chambers. A heat bank sealer 4654 is located within the upper vacuum chamber 4648. Sealing device is also attached to a pneumatic cylinder that provides motion in an upward and downward fashion. Sealing device is profiled to provide a flat strip like surface, horizontally disposed, that corresponds to the flange of the tray and can apply pressure downwardly onto the flange.

[0779] Second station 4656 includes lower clamp 4658 and upper clamp 4660 with ports 4652 for providing any suitable gas or for pulling vacuum. Clamps 4658 and 4660 are attached to a pneumatic cylinder and can be operated such that when moved toward each other a single sealing plate 4636 is clamped therebetween. A sealing device is located within the upper clamp 4660 with pneumatic cylinders attached thereto and a cutting device 4662 is located on the outer perimeter of heat bank 4664 and on the inside of 4660. Members 4662, 4660, 4664, and 4658 can be moved independently and in vertical directions. A winding arrangement 4666 is mounted above the conveyor and is powered by an electric driver to wind skeletal scrap web material.

[0780] In one instance, a sequence of operation of the packaging machine is as follows. Sealing plate 4636 attached to the conveyor 4670 with a loaded tray 4647 contained therein is indexed into position in first station 4646. Lid material 4643 is unwound from roll 4644 and located above tray 4636. Chambers 4650 and 4648 are clamped together with seal plate and tray clamped therebetween. Air is substantially evacuated from the vacuum chambers which are then filled with carbon dioxide gas or a blend of carbon dioxide and nitrogen. The gases are pressurized to a pressure above atmospheric pressure to about 25 psi and held for a period exceeding about one second. Pressure of the gas in the chambers is reduced to about atmospheric pressure and sealer 4654 is lowered so as to clamp the lid material against the flange portion of the tray. The lid material is then sealed thereto along the complete path of tray flange. Vacuum chambers 4648 and 4650 open and the conveyor indexes forward until another sealing plate 4636 is located at first station 4646 while the previously sealed tray can advance to a second station 4656, between upper clamp 4660 and lower clamp 4658. Clamps 4660 and 4658 close together thereby clamping sealing plate 4636 between the clamps. Sealing device 4664 is lowered to seal the lid material to tray at flange and cutting device 4662 is also lowered and retracted thereby severing the tray and package from web while the tray is still located in the sealing plate 4636. Skeletal scrap is wound onto scrap winding spool 4666. Conveyor continues to index forward and at one point packages are ejected therefrom. A tray constructed according to the present invention provides a peelable lib to introduce oxygen at a predetermined time, thus extending the shelf life of the perishable good stored therein.

[0781] 3.3.5. Embodiment

[0782] Referring now to FIG. 145 and FIG. 146, a plan view and a side elevation view of an apparatus designed to slice meat while conditioning in an oxygen free environment is shown. The apparatus is shown in diagrammatic form and includes a continuous conveyor 4700, with a driver mounted to a rigid frame (not shown) and horizontally disposed to allow horizontal motion in a machine direction in intermittent or continuous movement. The conveyor 4700 is fitted with two corresponding and vertically opposed pairs of pressure chambers, generally denoted by 4716 and 4717. Upper chamber 4702 includes a corresponding lower chamber 4704 and upper chamber 4706 includes a corresponding lower chamber 4708. An enclosed gassing tunnel 4718 is arranged to enclose the upper section of the conveyor 4700 with a gassing port 4712 affixed thereto to provide any suitable gas, such as nitrogen gas or carbon dioxide, into the tunnel 4718.

[0783] Referring now to FIG. 146, upper chamber 4702 and corresponding lower chamber 4704 are arranged so as to open and close in vertical alignment with one another. Upper chamber 4702 is mounted to a driver (not shown) to provide elevating, and lowering of a clamping apparatus. Lower chamber 4704 is also mounted to a separate driver (not shown) to provide elevating, lowering and clamping to upper chamber in a manner described above. Chambers 4702 and 4704 can be closed together by moving in opposing directions so as to contact each other along a path around the perimeter of openings. In this way, a single chamber is so arranged in a manner that is airtight and sealed from external atmosphere. An evacuation port 4714 and a gas port 4716 are provided so as to allow evacuation and gas flushing of the closed chamber. As shown in FIG. 146 two separate pressure chamber assemblies are arranged such that conveyor 4700 passes through both chamber assemblies. Trays with sliced beef or other meat primal, placed therein, are located into carrier plates in conveyor 4700. In one aspect, primals can be sliced in a suitable manner and can then be opened so as to expose the multiple surfaces of the slices immediately prior to entry into enclosed tunnel 4718. Enclosed tunnel 4718 is arranged so as to substantially exclude atmospheric oxygen gas by flushing other suitable gases therein.

[0784] The trays with sliced primal 4722 are located in carrier plates and progressively move through enclosed tunnel 4718 until each tray with primal is located directly between an upper chamber 4702 and lower chamber 4704. The upper and lower chambers close together and around the sliced primal 4722 in an airtight and sealed manner. Substantially all air is evacuated from the chambers and a suitable gas, including carbon dioxide, is injected through port 4716. The suitable gas pressure can be increased to any suitable pressure as desired. The primal 4722 can be retained in the pressure chambers for a desirable period of time so as to cause sufficient carbon dioxide gas to dissolve in the oils and water contained in the primal 4722. After the primal 4722 has been exposed to the high pressure carbon dioxide gas for a suitable period of time, the pressure chambers open and allow conveyor 4700 to carry sliced primal 4722 in tray, forward in machine direction and through the enclosed tunnel 4718. A second pressure chamber assembly may also be closed around the sliced primal 4722 in tray. Any suitable gas at any suitable pressure can be provided in the second enclosed chamber. Second chamber includes an evacuation port 4715 and a gassing port 4717. The sliced primal 4722 in tray is intermittently carried through the tunnel 4718 until it emerges at the exit end of the tunnel. In this way, formation of oxymyoglobin is inhibited when the primal 4722 is exposed to ambient atmosphere.

[0785] 3.3.6. Embodiment In one aspect of the invention, a gas padded packaging conduit is provided for the substantially oxygen free packaging of perishable goods. Referring now to FIG. 147, a schematic, cross sectional illustration of a section of a packaging conduit is illustrated.

[0786] The conduit is located on a factory floor 4800, and at a convenient elevation from the floor, in an enclosed, suitably ventilated room that is temperature controlled at about 38° F. in one instance. A generally horizontally disposed conduit is defined by an outer, substantially gas tight enclosed conduit 4801. Conduit 4801 includes varying modifications as will be described herein to accommodate various apparatus. Packaging components such as tray performs 4821 and web materials 4811, and ground meat 4827 are transferred into the conduit 4801 in such a manner so as to substantially exclude the entry of atmospheric oxygen by the introduction of a purge gas 4832 provided in any space inside conduit 4801 that is not occupied by equipment or goods. It is to be appreciated that all seals may not be substantially leak proof and therefore purge gas 4832 may be continually replenished so as to provide a gas padded enclosure. Gas 4832 is selected and may comprise any suitable gas such as carbon dioxide or nitrogen and is maintained at a pressure above ambient atmospheric pressure. A conveyor 4824 is conveniently mounted within conduit 4801 and arranged to carry trays 4820 therethrough.

[0787] Tray pre-forms 4821 are stacked into profiled and vertically disposed magazines 4823 and 4899. Magazines 4823 and 4899 are mated to conduit in a manner that substantially seals the magazines 4823 and 4899 to the conduit 4801 to reduce the loss of padding gas therefrom. Magazines 4823 and 4899 are arranged to have an outer wall that closely, but not substantially touches, and follows the outer profile of the stacks of pre-form trays 4821, contained therein. De-nesting mechanisms (not shown) are arranged to remove a single perform tray from the bottom of a stack, such as is contained in magazine 4823 and position it onto conveyor 4824. In this way, gas contained within conduit 4801 can then fill the cavity in the tray pre-form and thereby substantially prevent any atmospheric oxygen or other undesirable gases from entering into the tray cavity. Tray pre-forms 4821 are then carried in the direction shown by arrow 4831 to a position below the folding and bonding assembly not shown but housed within enclosure 4817. During the folding and bonding of pre-form 4821 to form tray 4820 gas 4832 fills all cavities or interstitial voids, or cells contained in the tray and tray materials and in this way it is ensured that only a selected and suitable gas is contained therein. Finished empty trays 4820 are then placed by folding and bonding assembly 4817 onto conveyor 4824 and carried forward to be loaded with portions of ground meat 4827.

[0788] A stream of selected ground meat is transferred through conduit 4803 in the direction of arrow 4829 at a convenient velocity and into fine grinder 4828 and in such a manner so as to extrude a continuous and suitably cross sectional profiled stream of ground meat 4804 onto conveyor 4824. Extruded stream 4804 is extruded into conduit 4804 and onto conveyor 4830, mounted therein, at a suitable velocity so that guillotine 4826 can cut portions of substantially similarly sized ground meat sections there from. Portions of ground meat 4827 are then transferred into trays 4820 which are together transferred through conduit 4801 on conveyor 4824. Conveyor 4824 can be arranged with upwardly disposed “cleats” 4880 or a series of suitable sealing plates to ensure that when ground meat portions 4827 are loaded into trays 4820 the tray is positioned precisely beneath the respective ground meat portion, allowing accurate loading into tray 4820 to produce a loaded tray with goods 4850.

[0789] Loaded trays with goods 4850 are then transferred through conduit 4801 toward over wrapping equipment arranged to over wrap trays 4850. A roll of suitable over wrapping web material 4810 is conveniently mounted above conduit 4801 and is unwound by transferring a single web of material 4811 through a slot like conduit 4812. Gas contained in conduit 4801 at an elevated pressure can pass over the surfaces of web 4811 while it passes through slot like conduit 4812 and in this way ensure that substantially no atmospheric oxygen is allowed to enter conduit 4812 or conduit 4801.

[0790] Over wrapped and hermetically sealed trays 4852 are transferred along conduit 4801 toward robot stacking arrangement 4814. Robot 4814 is enclosed in a housing that forms a part of conduit 4801 and is programmed to stack trays 4852 into groups 4815 that are then loaded into gas barrier containers 4813. Gas barrier containers 4813 can be formed in line and flushed with a suitable gas prior to loading of stacks 4815 therein. Horizontal thermoforming machine 4816 may be located conveniently below robot 4814 and arranged so that the thermoformed barrier containers 4813 are enclosed within an extension of conduit 4801 and thereby ensuring that gas 4832 is in contact there while forming barrier containers and filling cavities in the barrier containers 4813.

[0791] In another aspect of the present invention, an enclosed tray flap folding bonding apparatus is provided.

[0792] Referring now to FIG. 376 the tray de-nesting apparatus portion of FIG. 147, before the pre-form flaps have been bonded to the tray walls, is shown in a cross sectional view. Vertically disposed magazine walls 4823 are arranged to closely conform to the outer edge perimeter of the stacked pre-forms 4821. A narrow gap is thereby maintained between the stack 4821 and magazine walls 4823 allowing the tray pre-forms to slide through the magazine without restriction, as the lowest tray performs are progressively removed and placed onto conveyor 4824. Gas 4832, from conduit 4801, is exhausted through the narrow gap at 4840 and additionally selected gas such as 4832 can be injected through conduits 4822 at a suitable pressure so as to substantially fill spaces between the stacked pre-forms as they are gradually transferred through magazine 4823.

[0793] 3.3.7. Embodiment

[0794] Referring now to FIG. 148 a side elevation of an apparatus for packaging trays with fresh meat products constructed according to the present invention is shown in schematic form. This apparatus may be used to seal lidding material 4953, which may be a suitable grade of pPVC, to the flanges of trays (such as is shown in FIG. 94) wherein the apparatus is employed as an alternative, for example, to flow wrappers shown as in FIG. 176 herein. A rigid base 4950 is constructed from suitable materials such as stainless steel providing a suitable structure to mount horizontally disposed first and second conveyors 4970 and 4969 there upon. The first conveyor 4970 is driven by a driver (not shown) at a first speed, and the second conveyor 4969 may be driven by the same driver as drives first conveyor 4970. However, second conveyor may advantageously be driven at a second and suitably faster speed than first conveyor. Alternatively, second conveyor may be driven by a second driver (not shown), similarly configured to be driven at a speed which is faster than the speed of the first conveyor. A person of ordinary skill in the art would readily appreciate a suitable arrangement for accomplishing first and second driven conveyors.

[0795] A conduit 4958, suitably fashioned of a transparent material, is provided over the conveyors, and fastened in any manner readily available to the base 4950. The conduit 4958 is arranged so as to be substantially gas tight and sealed in such a manner that any suitable gas 4951 can be provided within the conduit 4958 so as to substantially eliminate oxygen from within the conduit 4958. The conduit 4958 may be directly connected to the previous upstream and subsequent downstream equipment to reduce the amount of gas that is lost at the entry and exit ends of the conduit 4958. Trays 4957 loaded with perishable goods, processed and portioned in any manner described herein can be transferred through conduit 4958 along conveyors 4970 and 4969 at a controlled rate or velocity as previously described. Conveyors 4970 and 4969 are arranged to carry trays in a direction shown by arrow 4980. A first, suitably narrow slot 4987 is provided on the upper side of conduit 4958 between sections 4956 and 4977 so as to allow passage of web material 4953 there through but to also minimize the quantity of gas that may escape from conduit 4958.

[0796] Any gas that escapes from conduit 4958 can be automatically replaced from a suitable source attached directly to conduit 4958 and wherein the source of gas is controlled by suitable valves and pressure gauges and switches arranged to ensure that a selected gas pressure is maintained in conduit 4958. A suitable gas pressure can be any pressure above atmospheric pressure to about 16 psi.

[0797] Sections 4976 and 4977 are arranged in close proximity and angled at a suitably inclined disposition so as to allow web material 4953, that is unwound from either of first or second rolls 4952 and 4954, to be carried through said slot 4987. Rolls of web material 4952 and 4954 are mounted upon an unwind assembly that can be arranged to automatically splice the end of one roll to the start of the other and in such a way so as to provide a continuous web of material. Any suitable splicing apparatus may be used to continuously provide lidding material 4953 without the need to stop production. Such apparatus is suitably provided by Hitech Systems Srl of Torino, Italy (www.hitechsystems.it). When the lidding material is pPVC, suitably, a stiffening material, such as duct tape or the like, may be applied laterally at the end of the first roll 4952 and at the beginning of the second roll 4954 to facilitate the automatic splicing of the first roll 4952 to the second roll 4954. When the need arises, the speed of the conveyors 4970 and 4969 or the takeup assembly 4965 may be speeded up or slowed down to prevent the spliced portion containing the stiffening material to form any part of a tray lid. The unwind assembly is securely mounted to a vertically disposed, rigid backing plate 4955. A suitably profiled housing 4981 is mounted to conduit 4958 in a substantially gas tight manner on an upper portion thereof. A carousel style assembly, comprising a vertically disposed circular plate 4961 mounted to a cantilevered shaft 4959 with sealing assemblies 4982, 4962 and 4983 mounted thereto, is located within housing 4981. A second, suitably narrow slot 4988 is provided on the upper side of conduit 4958 between sections 4979 and 4978 so that after sealing the web 4953 to the tray 4957, the used or remaining web material 4964 (which is a continuation of web 4953) therethrough minimizing the quantity of gas that may escape from conduit 4958. The second slot 4988 is suitably located at a position near the exit of conduit 4958, and near the end that is opposite the first slot 4987, so as to allow the remaining web material 4964 to exit the conduit 4958. Section 4979 and 4978 are arranged in close proximity and angled at a suitably inclined disposition so as to allow used web material 4964 to be carried through said slot 4988 and then wound onto either of rolls 4963 or 4965.

[0798] Rolls of remaining web material 4963 and 4965 are mounted upon a winder assembly that can be arranged to automatically splice the end of one used roll of web material onto the alternative roll winder in such a way so as to provide a continuous winding of remaining web of material 4964. The splicing of the remaining web material 4964 may take place in a manner similar to that described for splicing the unused lidding material 4953 on rolls 4952 and 4954. The winder assembly is securely mounted to vertically disposed and rigid backing plate 4960.

[0799] A longitudinally disposed parallel pair of continuous gripper chains 4971 (note that only a single chain can be seen in FIG. 148, however, the cross sectional view shown in FIG. 150 shows both gripper chains 4971 and 4931), are held in tension by a series of guides and sprockets 4956, 4986, 4967, 4966, 4968 and 4972. The chains extend longitudinally at least partially to coincide with the area of the first and the second conveyor. At least a single sprocket in each continuous gripper chain is spring loaded in such a manner so as to ensure a suitable degree of tension is maintained in each gripper chain. The gripper chains may be driven by a suitable servo electric motor at a suitable speed that is determined and controlled by a central processing unit (CPU) or PLC (Programmable Logic Controller) and in such a manner that is suitable for effective operation of the packaging apparatus. For instance, the gripper chain may travel at the same speed as the first conveyor 4970. However, the chains may be sped up under certain circumstances, for example, at the end of a web roll to avoid the spliced portion of the two ends of rolls 4952 and 4954. The gripper chains, which may be purchased from several chain manufacturers, such as Iwis of Germany, are arranged with web grippers that open as the chains pass around the sprocket 4956 and allow the continuous gripping of one edge of web material 4953. The two continuous gripper chains (as represented by 4971) are arranged to grip both edges of web material 4953 and carry it through slot 4987 and along the upper side of conduit 4958, and parallel thereto, and above trays 4957. A suitable level of longitudinal tension may be induced in web 4953, after unwinding from roll 4952 and prior to gripping by chains as represented by 4971, by providing a retarding or braking means to roll 4952. In this way trays can be carried along conveyors 4970 and 4969 at substantially the same speed as, and in the same direction to web 4953.

[0800] Referring again to carousel assembly mounted in housing 4981, three sealing assemblies 4982, 4962 and 4983 are mounted to rigid backing plate 4961 which is, in turn, mounted to shaft 4959. Shaft 4959 is rotated in the counterclockwise direction shown by arrow 4989, by a suitable servo motor (not shown) and at a speed that corresponds to the speed of both conveyor 4969 and web 4953. Assemblies 4962, 4982 and 4983 are similar and will be described in further detail herein below. Any suitable number of such assemblies may be arranged on such backing plate as 4962 but in this instance three are shown and mounted at pivot points 4974, 4973 and 4975 respectively. Furthermore, as the backing plate 4961 is rotated in a counterclockwise direction, the lower face of each assembly 4962, 4982 and 4983 is arranged to maintain a parallel disposition to web 4953. In this way, the lower face of each assembly can contact the web 4953 and apply a stretching force thereto prior to sealing to a tray and severing the web as described below. As trays are carried along conveyor 4970 and assemblies 4962, 4982 and 4983 rotate about shaft 4959 and successively apply stretching of web 4953 followed by sealing and severing of a portion of web 4953 to the flanges of each successive tray.

[0801] Referring now to FIG. 149 a cross section through a typical sealing assembly 4983 constructed according to the present invention, is shown. While sealing assembly 4983 is described in detail, it can be appreciated that sealing assemblies 4962 and 4982 are similar in contribution and therefore will not be described in detail. The assembly comprises a frame 4919 with pivot 4910, said pivot being fixed rigidly to frame 4919, but capable of rotating so the assembly can rotate about the pivot 4910. The frame 4919 is rigidly connected to a first backing plate 4920. Rectangular walls forming an outer stretching member 4913 are attached to the underside of the backing plate 4920. The walls forming the outer stretching member 4913 may be discrete or continuous so that member 4913 may include one or more discrete pieces. The stretching member 4913 includes rounded lower edges around the periphery of the lower open side. The lower open side of stretching member 4913 provides an opening which is suitably large enough to fit over the upper portion of a tray. The assembly 4983 also comprises an inner, rectangular profiled web sealing member 4917, having an inwardly sloping, angled face 4915. The member 4917 is mounted to a backing plate 4914 which, in turn is mounted to a pneumatic cylinder 4911. A rectangular profiled cutting member 4912 suitably corresponding to tray dimensions includes four cutting edges disposed along the lower peripheral edge. The member 4912 is mounted in interposed location between outer web stretching member 4913 and inner web sealing member 4917, and is fixed to a backing plate 4920.

[0802] Referring now to FIG. 150 a cross section X-X (see FIG. 148), through conduit 4958 constructed according to the present invention, is shown. A first gripper chain 4971 and a second gripper chain 4931 are arranged interiorly within the conduit 4958. The sections of chains 4971 and 4931 that travel in the same direction as the web 4953 are located in the upper portion of the conduit 4958. The sections of the chains 4971 and 4931 that travel in the opposite direction as the web 4953 are located in the lower portion of FIG. 150. In this manner, the forward moving chain sections may be the upper sections and the return sections may be the lower sections of the chains 4971 and 4931, so as to provide an endless continuous chain loop. The gripper chains 4971 and 4931 are suitably arranged on opposite lateral sides of the conduit 4958 and are configured to include devices capable of holding lateral edges of web 4953. The web 4953 is held between opposing upper chains 4971 and 4931 and the web 4953 is made taut there between by tensioning members 4924 and 4932 arranged so that respective upper edges 4926 and 4930 of tensioning members 4924 and 4932, respectively, are in tensioning contact with web 4953, i.e., the upper edges 4926 and 4930 are placed higher than the devices holding the lateral edges of the web 4953, such that the web 4953 is stretched. Tensioning members 4924 and 4932 are fixed vertically on a base 4939. The tensioning members 4924 and 4932 may run along the length of conduit 4958 in interposed position between the lateral conduit walls and conveyor sides for so long as tensioning of the web 4953. The upper chain sections are held captive in chain guides 4941 and 4942 but in such a manner so as to allow substantially unrestricted longitudinal chain movement along said chain guides and conduit. Trays, such as is detailed in FIG. 46 herein above, are carried along conveyors 4970 and 4969 at a suitable speed, which may be the speed that web 4953 is carried by the upper sections of the chains 4971 and 4931, so that the upper flanges 4943 of the trays 4957 are held in close and optionally touching proximity to web 4953. Conduit 4958 is mounted on a base 4940 and over conveyor 4969 and chains 4971 and 4931 in a substantially gas tight manner so that a selected gas 4951 which may substantially exclude oxygen, can be provided in the free spaces 4923 within conduit 4958.

[0803] Referring now to FIG. 151, a cross section through the flange portion of a tray similar in construction to that disclosed in association with FIGS. 46-49 herein above is shown. A vertically disposed, inner tray wall 4991 is shown terminating at a flange 4943. Flange 4943 slopes downwardly toward its outer edge to, in one instance, allow the stretch upper web 4953 to conform more readily to the flange and thus a more reliable hermetic seal. In some instances, the width of flange is not less than 1 mm and sometimes not less than 4 mm to provide a “target” for adhesive application. A flap 4993 is attached at hinge 4992. A bead of suitable cold seal adhesive 4990, such as a suitable latex compound, is provided as herein described above, along the full length of flange 4943 around substantially the entire upper periphery of tray and in such a manner so as to provide a hermetic seal with a lidding web 4953 after web 4953 has undergone stretching, sealing and severing of a suitable portion of web material from web 4953. Referring to FIG. 151, a web 4953 is shown, prior to sealing to flange 4943 of tray, but in contact with the tray flange 4943 at 4997, but is not in contact with cold seal adhesive bead 4990. A broken line 4995 is shown terminating at 4996 which represents the edge of lid web material after stretching of web 4953 with stretching member 4913, sealing with member 4917, and severing from web 4953 by knife 4912 shown in FIG. 149.

[0804] Referring to FIG. 148, sealing assembly is thus meant to operate in the following manner. Conveyors 4970 and 4969 position a tray 4957 underneath a sealing assembly 4962, 4982 or 4983 as shown in FIG. 148. As backing plate 4961 is rotated about shaft 4959, a sealing assembly such as sealing assembly 4983 is lowered over the tray. Within the sealing assembly, lower rounded edges of stretching member 4913 (FIG. 149) will stretch and displace web in a downward position on the insides of tensioning members 4924 and 4932 (FIG. 150). Further, while tray 4957 and sealing assembly 4983 continue moving forward in a direction indicated by arrow 4985 in FIG. 148, sealing member 4917 is lowered over tray 4957 by pneumatic cylinder 4911. Sealing member 4917 is suitably configured to dimensions which substantially correspond to tray flange periphery dimensions so that on activation of sealing member 4917, sealing member can depress web 4953 onto bead 4990, thereby hermetically sealing web 4953 to tray flange 4943. Sealing member 4917 may be retracted and cutting member 4912 cuts web 4953 around the periphery of tray 4957. Referring now to FIGS. 148-151, it can be seen that a lidding web material can be readily and effectively sealed, in an automated and continuous process, to the flanges of trays containing goods such as fresh meat.

[0805] 3.3.8. Embodiment

[0806] Referring now to FIG. 152, an alternative embodiment of an enclosed packaging conduit 4958′ is illustrated. This embodiment optionally uses ultraviolet radiation to cure the adhesive that bonds the lid material to the tray flange. This embodiment can further eliminate the need to have the sealing assemblies mentioned above. This embodiment uses a downward traveling chain assembly to bring the lidding material in touching proximity to the tray flange and thereby bond the lid to tray. The reference numerals used to describe the apparatus of FIG. 152 are similar to the ones used in the embodiment of FIG. 148 and denote like features. The operation of the enclosed conduit of FIG. 152 is similar in operation to the conduit of FIG. 148, but for some of the features described herein below.

[0807] Referring now to FIG. 152, as with the embodiment mentioned above, the packaging apparatus includes a pair of gripper chains 4971′, one located on each side of the conveyors or conveyor runs to hold the lidding material therebetween. In FIG. 152, a side view of the apparatus is seen. Because the gripper chains are located in substantially the same horizontal plane, only gripper chain 4971′ may be seen in FIG. 152. However, the other gripper chain is a substantial mirror image of gripper chain 4971′ and is located on the opposite side of the conveyors 4970′ and 4969′. At a suitable location along the conduit 4958′, the pair of gripper chains 4971′ are directed over roller 5099 and 5067. A roller that is a substantial mirror image of roller 5067 is located in approximately the same horizontal plane as roller 5067 on the opposite side of the conveyor 4969′. This roller guides the gripper chain also located on the opposite side of the conveyor from roller 5067 and gripper chain 4971′. Likewise, a roller that is a substantial mirror image of roller 5099 in form and function is located on the opposite side of conveyor 4970′ from roller 5099. As is apparent in the FIG. 152, only one gripper chain 4971′ and one roller 5067 is shown, but the opposite side of apparatus contains similar features. After the chain 4971′ passes roller 5067, the chain is again directed upwards and over roller 4966′. As the gripper chain 4971′ is directed downward by roller 5067, the lidding material 4953′ is brought in direct contact with tray 4957 at station 5002. Station 5002 can suitably be an ultraviolet source to cure UV-curable adhesive, which can be supplied by the National Starch and Chemical Co.; however, any other suitable adhesive can also be used in the present invention. The application of UV curable adhesive can suitably take place at a station having a frame with a ring containing the adhesive. As each tray passes below the frame, a suitable lifting arm or other lifting apparatus elevates the tray through the frame to bring the tray flange in contact with the ring holding the adhesive, thusly applying adhesive on the flange surfaces of the tray. However, other alternatives to apply adhesive on a tray flange can be realized. For instance, with slight modification the ring can be lowered to the tray; or other methods may apply the adhesive with a spray or roller carrying the adhesive. Before the lidding material 4953′ is laid on the flange carrying the adhesive, the lidding material 4953′, at this point is suitably pre-stretched, so as to prevent the wiping of adhesive from tray flange. Lidding material 4953′ can then be bonded by curing the adhesive with the UV source 5002.

[0808] Referring now to FIG. 153, a cross sectional view taken along the length of the enclosed packaging conduit 4958′ where the lidding material 4953′ is brought into contact with the tray flange is schematically illustrated. As is evident from the FIG. 153, the enclosed packaging conduit 4958′ is attached to a base 4940′. Conveyor 4969′ and 4970′ are included within the conduit 4958′. The conduit 4958′further includes a pair of continuous gripper chains 4931′ and 4971′. As previously described, the gripper chains catch on to either side of the lidding material and thereby stretch the lidding material before it makes contact with the tray flange. However, the lidding material is not stretched appreciably after the lidding material makes contact with the tray flange because the upper sections chains 4971 ′ and 4931 ′ may be directed inward toward the tray. The upper and lower sections of gripper chain 4971′ are part of the same chain that form one continuous loop. However, the upper section of chain 4971′ is traveling in an opposite direction as the lower section of chain 4971′, thusly forming the continuous loop, while chain 4931′ forms a similar continuous loop traveling in the same direction on the opposite side of the conveyors 4969′ and 4970′. The chains function similarly to the embodiment described above, i.e., to carry and apply tension to the lidding material 4953′ in a traverse, or side to side fashion. As can be seen in the FIG. 153, the conduit also has a pair of devices 5099 and 5098 that are suitably configured to trim the lidding material 4953′ along the longitudinal direction. Also present (but not shown) are trimming devices that trim the lidding material along the traverse direction, i.e., front and back. Suitably, the front and back trimming of lidding material 4953′ occurs before the trimming of the side material. However, other embodiments may have the trimming carried out in the reverse manner.

[0809] The conduit may also include one or a plurality of radiation sources 5006, 5008, and 5005, located either internally or externally to the conduit 4958′. Such sources, may provide ultraviolet, infrared or microwave radiation for one or more purposes. For instance, infrared may be used to reflow an adhesive that has hardened or solidified. Ultraviolet or microwave radiation may be used to cure an adhesive.

[0810] The means for bringing the lidding material in touching proximity to the tray flange includes a pair of guide members 5013 and 5004 located on opposite sides of the conveyor 4969′. It is important to note that station 5002 is located above conveyor 4969′, therefore the conveyor in FIG. 153 has been labeled 4969′. However, because conveyors 4969′ and 4970′ are arranged linearly and the cross section occurs at a location adjacent to conveyor 4970′, the conveyor section in FIG. 153 also corresponds to conveyor 4970′. However, guide members 5013 and 5004 are angled or sloped, meaning that they originally begin at a higher position, generally, beginning above the lidding material 4953′, and thereafter sloping downward and directing the lidding material to a lower position which generally ends at a position that is below the base of tray 4957. The upper surface of the lidding material suitably contacts the guide members 5013 and 5004 and as lid material 4953′ is carried forward, it may be directed downward until the lid material directly above the upper flange of the tray 4957 makes contact with the upper flange on tray 4957. As lid material is directed downward, if chains are not directed inward, lid material would undergo significant tensioning, therefore chains 4971′ and 4931′ can be directed inward at the same time they are directed downward to maintain the appropriate amount of tension in lid material 4953′. As the chains are directed inward the resulting tension in the web material may be more or less than tension originally imparted by chains on the lid material before the lid material was directed downward.

[0811] The guide members 5013 and 5004 in addition to bringing the lidding material to the tray flange also cause the lidding material to lay against the sides of tray 5009. The lidding material can then be partially relaxed, for example, by directing the gripper chains 4971′ and 4931′ further inward. Another station may then bond lid material to the exterior tray walls 5009 (described in more detail below). To this end, guide members 5013, 5004 serve to press lid material to the exterior of the tray wall 5009 along two sides thereof by their sloping character. Before or after bonding of lid material to the side walls of the tray, lidding material 4953′ may be severed from continuous roll in both the traverse and longitudinal directions. A suitable cutting devices 5099 and 5098 are positioned to trim the lidding material 4953′ at a location approximately at tray base level. Other cutting devices (not shown) can sever the web material at transverse locations. As described above, the adhesive for this purpose can be any suitable adhesive, such as, but not limited to a pressure sensitive adhesive. If the adhesive is in need of reflowing or to add tackiness, the adhesive can be reflowed by devices 5008 and 5005, which can be infrared or ultraviolet sources. The guide members are suitably constructed out of circular solid metal which can be optionally coated with a lubricating material, such as, but not limited to Tufram or Teflon, to prevent binding or sticking of the lidding material to the guide members 5013 and 5004 as the lidding material travels in a forward and downward direction. Prior to the lidding material being applied to the tray flange, an earlier stage in the package formation applies an adhesive to the tray flange. A non-limiting example of a suitable adhesive includes a UV curable adhesive supplied by National Starch and Chemical Company of Bridgewater, N.J.

[0812] Referring now to FIG. 154, a top plan view of a suitable embodiment of lidding material 4953′ useful in sealing a tray is illustrated. Optionally, the lidding material or web can be printed by any suitable means. The lidding material 4953′ can include a plurality of regions, 5019, 5017, 5098, and 5022, appropriately called lid material flaps so as not to be confused with tray flaps. The lid material flaps are locations or regions located in the lidding material that will be adjacent to the tray walls 5009 when the lidding material is pressed against the tray walls 5009. The lid material flaps 5019, 5017, 5098 and 5022 can include any printed material. Without limitation, the printed material can include information regarding the source of origin or ownership or specifications concerning any information or advertising pertaining to the product contained within the package. Furthermore the lid material flaps may be colored coded according to the product that is being contained within the tray. In one embodiment, particular to some European countries the flaps are colored pink for pork, yellow for chicken, blue for fish, etc. However, any color code particular to any recognized standard is within the scope of the invention. The lidding material may come preprinted with the color coded regions, or the regions may be colored along the length of the enclosed packaging conduit. The lid material flaps 5019, 5017, 5098, and 5022 can suitably be bonded to the side walls of the tray 4957, while a window 5020 or clear unprinted portion of the lidding material can provide viewing of the contained package contents. As shown in the FIG. 154, the dashed lines bordering lid material flaps 5019, 5017, 5098 and 5022 indicate approximately the locations where the cutting devices 5099 and 5098 will sever the lidding material from the tray after the lidding material has been sealed to the tray walls 5009. Gripper chains 4971′ and 4931′ are shown placing tension on lid material 4953′ as the material is being applied to the underlying tray 4957.

3.3.8.1. Embodiment

[0813] In an enclosed packaging conduit, one aspect of the present invention is to provide an adhesive that can be used to seal both the tray to the flap and the web lid to the tray. One aspect of the present invention is to apply adhesive on the tray flange, when the tray flaps are folded. One aspect of the present invention is to apply adhesive around the base and flange of the tray. One aspect of the present invention is to rotate the tray 90 degrees, so as to complete applying adhesive for box shaped trays. One aspect of the invention is to laterally and longitudinally stretch a web lid 10 to 20% before applying the lid to the tray. One aspect of the invention is to bring the web in contact with the tray while under tension. One aspect of the present invention is cut the web on three sides thereof when the web is bonded at the adhesive. One aspect of the present invention is to relax the lateral tension after the cutting step to about 5 to 10% stretch. One aspect of the present invention is to cut and roll the web lid onto the sides of the tray. One aspect of the present invention is to release the web lid from the gripper chains. One aspect of the present invention is to overlap an upper corner of the tray with the web lid. However, overlapping of the lower tray corners can also be undertaken. One aspect is to take up any scrap web with a vacuum device.

[0814] While one example has been provided of the events that may occur in the present invention, it is to be appreciated that more or less steps can be undertaken, the ones mentioned herein being merely an example of one embodiment.

3.3.8.2. Embodiment

[0815] In another aspect of the present invention, a plurality of different adhesives may be used to construct and seal a packaging tray in an enclosed packaging conduit, such as the embodiments disclosed herein above. These adhesives may be selected depending on the ultimate use in the package. For example, a UV curable adhesive can be used to bond the lidding material 4953 to the tray flange 4957. Such an adhesive can be obtained from the National Starch and Chemical Company of Bridgewater, N.J., under the mark CONTOUR. This adhesive can come as 100% solid, with little to no water, can be a heavy liquid or hot melt and is cured by ultraviolet radiation. The ultraviolet radiation suitably penetrates a transparent member to reach the adhesive. A hot melt adhesive or microwave curable adhesive may be used to weld the tray flaps to the sides and bottom of the tray as will be described below, and a pressure sensitive adhesive may be used to hold the lidding material flaps to the sides of the tray package. This is advantageous because not all bonding operations may desirably be occurring at the same stage of packaging. For example, the tray flaps may have been bonded to the tray prior to entering the enclosed packaging conduit 4958. However, with slight modifications, the conduit 4958 may accommodate a tray flap folding and bonding station. Suitably, pressure sensitive adhesive may be applied to the sides of tray flaps to bond with the lidding material. These adhesives may also suitably be provided before the entrance of the tray package to the conduit 58. However, again with slight modification, the conduit 58 can be made to accommodate any adhesive application station, such as the use of sprayers or rollers. Also suitably, since any selected adhesive may lose its tackiness or may harden over time, this condition can be corrected to cause re-flow or re-melt of the adhesive by the use of heaters located along the exterior or interior sides or top of the packaging conduit 58. Under certain conditions, it may be desirable to cause such adhesives to harden, for example, a hardened adhesive will have minimal flow, thus, it will not smear or attach itself if it is accidentally contacted with foreign substances. Suitable adhesives may be any of the rubber based adhesives that can suitably be reflowed.

[0816] In another aspect of the present invention, bonding may take place with any suitable adhesive that is capable of withstanding the temperatures that may be encountered in a microwave oven. In this manner, the whole tray may be placed in the microwave oven or any heat convection oven. One suitable adhesive includes crystallizable PET.

[0817] In still another aspect, the stretch sealing machine as disclosed above, can stretch a web, and after adhesive has been applied to tray, the web is bonded to the tray on contact in a tensioned state.

3.4. Vacuum chambers

[0818] In one aspect of the invention, vacuum chambers are provided with the packaging apparatus herein described above, for the evacuation of oxygen or other undesirable gases from trays and flushing with a desirable gas to enhance the shelf life of perishable goods.

[0819] 3.4.1. Embodiment

[0820] FIG. 155 shows a cross-section through one embodiment of a vacuum assembly constructed according to the present invention. The vacuum chamber assembly includes a first upper 5124 and a second lower 5116 vacuum chamber portion. Sealing plates 5118 disclosed herein may be first arranged on a conveyor that is driven by any suitable motor as required providing intermittent movements of the conveyor. Lower vacuum chamber 5116 is independently moved by a pneumatic driver (not shown) so as to apply pressure to underside of sealing plate 5118. Plate 5120 is located between sealing plate 5118 and plate 5122. Plate 5122 has vacuum port 5130 provided therein. Upper vacuum chamber 5124 is located above plate 5122. All components are in vertical alignment and when lower chamber 5116 and upper chamber 5124 are retracted and moved in the vertical plane away from each other, plates 5118, 5120 and 5122 may be spring loaded and also “expand” away from each other so as to allow free movement of the tray 5136 and first 5132 webs between plate 5120 and plate 5122 or between plate 5118 and plate 5120 as may be selected according to requirements or operation of apparatus. As is shown in FIG. 155, second web 5134 enters the vacuum chamber assembly between plate 5122 and upper vacuum chamber portion 5124 and exits the vacuum chamber assembly between plates 5120 and 5122. Also, it can be seen that first web 5132 enters vacuum chamber assembly between plates 5120 and 5122. A space 5138 is shown between the first 5132 and second 5134 webs with port 5130 opening into space 5138.

[0821] During the operation of the packaging apparatus, after closing of lower vacuum chamber 5116 and upper vacuum chamber 5124 toward each other thereby providing a closed and sealed vacuum chamber, a vacuum source can be applied to port 5130 and thereby evacuate substantially all air from the space 5138 between the first web 5132 and the second web 5134. Evacuation of air from space 5138 can cause first 5132 and second 5134 webs to become laminated together after removing substantially all air from the space 5138. Slots shown as 5140 are provided between the faces of plates 5116 and 5118, 5118 and 5120, 5120 and 5122, and 5122 and 5124. These slots provide spaces between each of the components, “O” rings are fitted along the outer edges of each slot to provide a seal when the components are in contact with each adjacent component. A vacuum source can be applied to each of these spaces, simultaneously, thereby providing a method to hold them together with a force equal to that provided by the ambient atmospheric air pressure prevailing at the time. The holding force that urges the components together is therefore approximately equal to the width of the slots between each component, times the length of the slot, multiplied by the difference of the prevailing atmospheric air pressure minus the air pressure within the slots defined by the equation:
F=WL(P_a−P_s)
wherein,

[0822] F is the force,

[0823] W is the width of the slot,

[0824] L is the length of the slot,

[0825] P_a is the atmospheric pressure, and

[0826] P_s is the pressure inside the slot.

[0827] It should however, be apparent that other configurations are possible. The width of each slot can be arranged, by enlarging (or decreasing) so as to provide a level of force that exceeds the desired and opposing force of gas pressure within the closed chamber. A pair of “O” rings are also provided around all shafts that penetrate the chamber and spaces provided between each pair of “O” rings can also be evacuated. In this manner, the vacuum chamber can be used to eliminate ambient air, oxygen or any undesirable gas and replace it with a suitable gas of suitable composition, in one instance, being mainly carbon dioxide.

[0828] In another aspect of the present invention, the space 5138 provided between webs 5134 and 5132 can be eliminated prior to the webs entering the vacuum chamber assembly 5100. Referring momentarily to FIG. 156, a cross-sectional view through a laminating assembly 5147 including a first 5148 and second 5150 rubber coated roller arranged in horizontal disposition and with devices (not shown) urging them toward each other so as to press and laminate the first 5132 and second 5134 webs when the webs are passed between the rollers 5148 and 5150. Rollers 5148 and 5150 are driven by a variable speed motor (not shown). Laminating assembly 5147 can be located before the vacuum chamber assembly 5100 to thereby provide a method to laminate first 5132 and second 5134 webs together before entering the vacuum chamber assembly 5100.

[0829] 3.4.2. Embodiment

[0830] Referring now to FIG. 157 a cross-sectional view through a vacuum chamber 5214 constructed according to the present invention is shown. The tray 5202, first 5204 and second 5206 webs are shown prior to sealing the webs together. This vacuum chamber has a plate 5254, separating first 5204 and second 5206 webs, at both the entrance and exit portions of the chamber for both the first and second, unlike the chamber of FIG. 155.

[0831] A system incorporating vacuum chamber 5214 may be configured as follows. Perishable product, such as beef, is loaded into tray (tray web 5202) and then each loaded tray is placed into apertures in sealing plate 5250. The conveyor indexes forward such that a loaded tray is located at first station 5214. During indexing, second web 5206 and first web 5204 are also indexed forward and a longitudinally disposed tension can be applied to second and first webs and in a direction parallel with the conveyor. Lateral stretching can also be applied to first web 5204 such that it is stretched taut. Upper vacuum chamber portion 5216 includes a plurality of clamp members to hold the first 5204 and second 5206 webs in position. Upper clamp member 5252 and lower clamp member 5222 close against the middle clamping plate 5254 thereby clamping and firmly holding second and first webs 5206 and 5204, respectively. Lower vacuum chamber 5220 and upper vacuum chamber 5216 are closed against the clamping plate assembly 5250 such that a substantially “airtight” seal is provided and the upward movement of lower vacuum chamber 5220 lifts sealing plate 5250 and holds it firmly against the underside of the lower clamp 5222 thereby providing substantially “airtight” seals around the perimeter of the upper and lower vacuum chambers 5216 and 5220. Closing the upper and lower chambers thereby defines a single enclosed chamber that is substantially isolated from atmospheric gases. During the procedure of closing the upper and lower chambers, the lower vacuum chamber 5220 lifts the sealing plate 5250 upwardly and tray (tray web 5202) is carried upward as well. The upper rim portion of sealing plate 5250 at 5258 contacts the underside of first web 5204 stretching first web upwardly until sealing plate 5250 contacts the underside of lower clamp 5222 thereby stopping the upward movement. The first web 5204 is now stretched taut across the opening of the ring 5258 and distanced about 1/64 to about ½ inches, or about ⅛ inch above a suitable tray flange and about 1/64 to about ½ inches, or about ⅛ inch below second web 5206.

[0832] Atmospheric air contained within the enclosed chamber is then substantially evacuated through evacuation ports 5208, to a pressure of less than 5 torr. Immediately after evacuation, the chamber can be filled with carbon dioxide gas, or a blend of carbon dioxide and nitrogen gases, to a pressure of up to 2 bar (28 psi) or more, by injection through ports 5264 and optionally 5208, and held at pressure for a period of 1 to 5 seconds or more and until water and goods in the tray have become substantially saturated with dissolved carbon dioxide. The gas pressure within the chamber assembly can then be lowered to a pressure equal to that of the prevailing ambient atmospheric pressure prior to sealing. Evacuation and gassing of the chamber assembly in accordance with the invention, provides a method of filling packages with a chosen gas such that the residual atmospheric oxygen that remains within the package does not exceed an amount about 0.05% by volume of the gas that remains within the package after sealing the tray 5202, first 5204, and second 5206 webs together.

[0833] Referring again to FIG. 157 in conjunction with FIG. 158 and FIG. 159, a clamping member 5236, that can be water cooled, can now be moved and positioned so as to clamp second web 5206 against first web 5204 and in turn against the flange portion 5272 on tray web 5202. A first heat bank 5224 at a first temperature can then clamp and heat seal first and second webs 5204 and 5206 to flange portion 5272 of tray web 5202, under pressure. Heat bank 5224 can now be retracted followed by cutting of first and second webs with cutting member 5240 attached to cutting device 5238. The cutting member is withdrawn from the cutting position followed by release of clamp 5236. Enclosed vacuum chamber assembly can then be opened allowing a conveyor to index forward to place another sealing plate with a tray web, followed by closing the vacuum chamber assembly, followed by evacuation, gassing and heat sealing. This cycle can be repeated in an automatic and continuous mode. Pneumatic cylinders are attached to shafts 5230 (attached to heat bank 5224), 5232 and 5228 (attached to water-coded clamp 5236) and 5234 and 5226 (attached to cutting device 5238), and provide independent reciprocating movements to each shaft and attachments generally in the vertical plane of motion. Similarly, pneumatic cylinders (not shown) are attached to upper 5214 and lower 5220 chambers to provide reciprocating movements parallel with shafts 5230, 5228, 5232, 5226, and 5234 to provide movement and apply pressure as required.

[0834] An optional method of using the apparatus whereby a gas is not provided in the space between second web 5206, and first web 5204 (so as to subsequently facilitate urging of the first 5204 and second 5206 webs together), before sealing the second web 5206, first web 5204 and tray web 5202. In this aspect, the tray web 5202 is elevated so as to urge first web 5204 toward the underside of second web 5206, thereby providing stretching means to first web 5204 and removing any air between the first 5204 and the second web 5206. Apparatus for evacuation of substantially all air from the space between the second 5204 and the first 5204 webs, through ports 5208 are therefore optional.

[0835] After the first and second webs are scaled to the tray web at flange 5272, it may be desirable to seal the first web 5204 to flange 5274 of the tray web 5202 as shown in FIGS. 158 and 159. The sealing apparatus 5316 described below may be used to create the seal.

[0836] 3.4.3. Embodiment

[0837] Referring now to FIG. 160, a cross-sectional view of sealing apparatus 5316, constructed according to the present invention is shown in a partially closed position.

[0838] Referring to FIG. 158 and FIG. 159, a cross-sectional view through a finished and sealed package constructed by the vacuum chamber 5214 is shown. Package 5292 includes a flange 5272 with first web 5204 and second web 5206 attached thereto. Shown is tray web 5202, formed with two flange portions 5272 and 5274. Flange portions 5272 and 5274 are adjacent and concentric to each other, with flange 5274 located on the inner side of flange 5272.

[0839] Referring now to FIG. 160, a sealing plate with package constructed by vacuum chamber 5214 is located beneath heat bank 5370. It can be seen that lip 5380 has a profile that corresponds to and follows the path and plan profile of flange portion 5274. A section of flange 5274 is more clearly seen in the enlarged cross-section in FIG. 159. Flange portion 5274 is parallel and concentric to flange portion 5272 but follows a path on the inner side of flange portion 5272 and at a plane shown to be at a distance 5276, about ⅛ inches below flange portion 5272. Heat bank 5370 is pneumatically operated and can extend downwardly and be retracted upwardly as required to exert a force such as to provide pressure onto the lip 5380 and when engaged with flange portion 5274, simultaneously depressing second and first webs that are then held, under a sealing pressure (sealing pressure), between the surface of flange portion 5274 and lip 5380 for a set period of time (set time). The temperature of heat bank 5370, and correspondingly lip 5380, can be controlled and is set at a suitable temperature (set temperature). The temperature of heat bank 5370 may be less than the temperature of the heat bank 5224 located in vacuum chamber 5214. Pressure is applied at lip 5380 and can be set at sealing pressure. The suitable time of contact and clamping of second and first webs to flange portion 5274 can be varied. Time of contact is defined as the length of time during each cycle from the first instant of first contacting between lip 5380 and flange portion 5274 through the second and first webs, to the first instant of no contacting after retraction of heat bank 5370. Thereby, when the set temperature, sealing pressure and set time of heat bank 5370 are adjusted as required, the selective heat sealing of first web 5204 to flange portion 5274 can be achieved while second web does not heat seal to first web. This can be achieved when tray, first and second webs include materials as described below.

[0840] Referring again to FIG. 158 and FIG. 159, a representation of an enlarged view of a section through a flange portion of an assembled package is shown. In one instance, second web 5206 is a co-extruded web including at least two layers with a first layer 5282 of Eastman PET 9921 and a second layer 5284 of material on the underside of the second web including a blend of 2 grades of Eastman polyesters in amounts of about 50% Eastobond 6763 and about 50% Eastobond 9921 or alternatively the layer on the underside may be about 520% Eastman PM 15086. Second web can be about 0.006″ thick, about equally divided between first and second layer. In one instance, first web 5204 is a web of pPVC with a thickness of about 0.0008″. In one instance, tray web 5202 includes a thermoformed tray produced from a multilayer co-extruded web with an outer layer of Eastman 9921 and an inner layer including a blend of about 50% Eastman PETG 6763 and about 50% Eastman 5116 (or Eastman PM14458 or equivalent). In one instance, tray web 5202 has a thickness of about 0.012″ where the inner layer is about 0.004″ thick and the outer layer is about 0.008″ thick. Under such conditions and materials, the heat transferred through second web is insufficient to cause bonding between the second and first webs but sufficient to cause bonding between the first and tray webs at flange portion 5274. Such arrangement provides stretching of first web, after sealing of second and first webs to tray web at the vacuum chamber 5214. Applying gas pressure to the upper surface of the second web, when located at sealing apparatus 5316, so as to cause the first and second webs to depress downwardly and substantially conform to the contours of flange portion 5274 prior to providing heat sealing the first web to flange 5274 provides an alternative means of providing contact between the first web and flange 5274.

[0841] In another aspect, first web 5204 will have a feature known as a “memory”. The term “memory”, in this context, is known in the packaging industry and is characterized as a material that will substantially return to its original shape after distortion has occurred due to, for example, a consumer “feeling” the goods contained within the package while the package remains intact, with first web sealed to the tray flanges. This can cause finger marks and depressions in the first web as prospective purchasers of the package examine it prior to purchase during retail display of the package. After excessive handling by consumers the package can become unattractive to an intending purchaser and financial losses can result therefrom. Materials such as polyethylene substantially do not have “memory”. However, plasticized PVC (pPVC) web materials, such as made by Borden do provide this desirable feature. First web constructed from pPVC may be perforated by perforating apparatus to improve gas transmission therethrough.

[0842] Perforations can be provided in first web 5204. The perforations can allow gas to permeate into a space between first web and second web. When the gas pressure inside the sealed package is at a pressure slightly above ambient air pressure, second web will be stretched outwardly into a dome shaped condition thereby providing a gas buffer between second web and the surface of goods beneath the first web. First web may be in contact with the surface of package goods, alternatively a space can be provided therebetween. The seal between first web and second web may be arranged such that it is not a continuous seal along the full path of flange portion 5274 and may be arranged as an intermittent sealing, completely along one or more sides only or parts thereof.

[0843] In yet another embodiment heat bank 5370 may be mounted at the vacuum chamber 5214, concentrically with and on the inside of heat bank 5224 within the same chamber but with separate moving shafts. Such an embodiment would allow sealing at flange portion 5272 and flange portion 5274 without the need to transfer the package from the vacuum chamber 5214 to sealing apparatus 5316 for sealing of flange 5274. Suitable web cutting devices are located at sealing apparatus 5316 to separate the sealed and finished package 5292 from webs if necessary.

3.5. Composite Lidding Materials

[0844] In another aspect of the present invention, a pre-stretched web of flexible gas permeable material laminated to a substantially more rigid gas barrier material is provided.

[0845] Referring to FIG. 161, first 5400 and second 5402 roll of web material including a first web 5404 and a second web 5406 are unwound simultaneously and laminated by passing the webs through a pair of “nip” rollers 5408 that apply pressure against each other in the direction of arrows 5415 and to the webs as they pass through nip rollers 5408. Nip rollers 5408 are driven by any suitably powered driver to rotate at a suitable speed. The laminated web 5412 is rewound onto a single roll 5410 together to produce a roll of laminated web 5412. Second web 5406 may include a semi rigid polyester material, of about 0.005″ to about 0.007″ thick. The construction of this material is such that it can be used in a packaging machine to produce packages as described herein whereby laminated webs, such as web 5412, are sealed to a tray web of gas barrier material (tray).

[0846] Tray web may have a depression formed therein into which goods such as red meat can be placed before heat sealing the second and first webs to the tray web. Goods will typically not completely fill the depression and space will remain in the depression in addition to the goods. A blend of gases or a single gas such as CO₂ can be provided in the space with goods and thereby can contact the goods. The gas substantially eliminates the presence of oxygen and any red color present in the red meat may be transformed to a purple color. This is caused in part by the reduction of oxymyoglobin to deoxymyoglobin. After storage of perhaps a period of 14-28 days from packaging but prior to retail display at an intended point of sale to consumers, the second web can be peeled from the package allowing atmospheric oxygen to permeate the first web of gas permeable material and to contact the goods. Atmospheric oxygen can then generate a bright red colored substance, such as oxymyoglobin. Such use involves the sealing of the laminated webs to the tray web of gas barrier material such as a two-layer co-extrusion where the outer layer includes Eastman APET 9921 of about 0.0035″ thickness, and the inner layer may is a blend of Eastman polyester materials including about 16% of 6763 and about 84% of 9921.

[0847] The thickness of blended layer 5412 can be about 0.0015″. First web 5404 includes a roll of monolayer pPVC with a thickness of about 0.0008″ to about 0.0012″. As first web 5404 is unwound it can be passed through a perforator 5414 that perforates the first web by creating small apertures therethrough. First web 5404 can be tensioned in a controlled manner by retarding the rate of unwinding of first web 5404 from roll 5400 relative to the unwinding rate of second web 5406 from roll 5402. Tension is thereby applied to first web 5404 of material prior to passing through the nip rollers 5408 at which point substantially all of the air between the two layers of material is forced out by the nip rollers 5408. The consistency and texture of elasticized PVC material included in first web 5404 is such that it adheres lightly to second web 5406 unwound from roll 5402 forming a very light seal that excludes all air from between the webs. First web 5404 is applied to the inner, blended layer of second web 5406, a substantially more rigid material unwound from roll 5402. In one instance, an anti-blocking agent, such as very fine sand, can be added to the second web upper or outer layer of the co-extrusion so as to inhibit sticking of first web to what will be upper layer such that first web will remain in close contact with what will be the underside of second web during storage in a roll 5410 condition and during unwinding from roll 5410 in normal operation on a packaging machine.

[0848] First 5404 and second 5406 webs, having been laminated to produce a lamination and subsequently wound onto the finished roll 5410 can be stored and when required for use in packaging can be loaded onto packaging machine as shown in FIG. 162.

[0849] Referring now to FIG. 162, a process to bond a laminated web of material 5412 to a tray web or tray is shown. The two webs include the second and first webs. The apparatus is suited to produce any packages herein described. Tray web 5416, preferably of a substantially gas barrier material is located into an aperture (not shown) in sealing plate 5418 mounted on the conveyor 5420. Tray web 5416 has a cup-shaped depression formed therein. Red meat or another perishable good is loaded into tray web 5416 and a plurality of trays are located into the apertures in each sealing plate 5418 mounted to conveyor 5420. The conveyor indexes forward such that a loaded tray is located between upper vacuum chamber 5422 and lower vacuum chamber 5424. During indexing of the conveyor 5420, the tray web 5416 is also indexed in a direction parallel with the conveyor and placed into position between upper 5422 and lower 5424 vacuum chambers. Upper 5422 and lower 5424 vacuum chambers are closed together such that sealing plate is clamped therebetween to provide a substantially sealed and enclosed chamber assembly. Air is evacuated from the chamber assembly to a pressure level of approximately 5 torr and a selected gas is injected into the chamber assembly. The gas being chosen for its properties of enhancing the keeping qualities of goods, in tray web 5416, such as carbon dioxide or a blend of carbon dioxide and nitrogen is suitable. Tray web 5416 is then bonded to laminated web 5412 to produce a package. Upper 5422 and lower 5424 vacuum chambers are then opened so that conveyor 5420 can carry sealed package to an ejection point. The package may be trimmed by cutting devices located within the chamber assembly such that a skeletal scrap web can then be wound onto a single wind-up spool, or alternatively, if it is desired to have similar materials only as a single roll, the scrap laminated web 5412 can be separated by de-laminating the second web scrap 5406 from first web scrap 5404 onto scrap wind-up 5426 and 5428, respectively. The package may be trimmed within vacuum chamber in one machine cycle or alternatively the package may be trimmed from the web in a second operation immediately after the vacuum chamber.

[0850] Tray web 5416 or tray may be thermoformed from co-extruded polyester plastic materials as shown in FIG. 163. Co-extruded material may include two layers of a total thickness of about 0.015″. The outer layer 5430 is about 0.0135″ thick and the inner layer 5432 is about 0.0015″ thick. The outer layer 5430 includes Eastman APET 9921 and the inner layer 5432 is about a 50/50 blend of Eastman 13162 and Eastman 6763.

3.6. Stretch Wrapping

[0851] In one aspect of the invention, methods and apparatus are provided to stretch a lidding material over a tray to produce a finished package. Stretch wrapping can occur under reduced oxygen conditions to provide for extended shelf life to products. Over wrapping can be heat sealed and/or adhesively bonded to the tray.

[0852] 3.6.1. Sealing Plates

[0853] In one aspect of the invention, stretching a web across the a tray is provided by a sealing plate. Any of the foregoing methods requiring a sealing plates can be provided with sealing plate of the following nature.

[0854] Referring to FIG. 164, a cross-section of a sealing plate 5550 constructed according to the present invention is shown with a plan view shown in FIG. 165. Sealing plate 5550 includes attachment points 5594. Attachment points 5594 may be used to attach the sealing plates 5550 to a pair of continuous chains that engage with sprockets located one at each end of conveyor. Sealing plate 5550 has a depth dimension that is about equal to or deeper than the depth of depressions in tray web, so that tray web does not protrude through the lower surface of the aperture 5530. A rubber seal 5535 is attached to the sealing plate 5550 by an adhesive and is profiled to provide flanges 5596 and 5598 that correspond to flange portion 5272 and flange portion 5274 of first tray web 5292 shown in FIG. 159. A space 5551 between the rubber seal 5535 and rim 5578 is provided to allow clearance for a cutting member during the cutting of the second and first webs after sealing to flange portions 5572 and 5574.

[0855] Referring now to FIG. 165, one embodiment of a sealing plate 5550′ is shown in top plan view. In the embodiment represented here, the sealing plate includes two apertures 5530′ to accommodate two trays. However, it is apparent that any number of apertures can be provided, depending on the desirability of including one or more apertures capable of carrying a plurality of trays, such as shown in FIG. 166, having three apertures 5530″.

[0856] Referring now to FIG. 167, a cross-sectional view of the details of sealing plate 5550″ with three apertures 5530″ is provided. As an example, this embodiment has three apertures 5530″ and rubber seals 5535″ located around the perimeter of each aperture is shown. However, sealing plates may have more or less apertures and corresponding rubber seals. Under some circumstances, rubber seals are made optional. Sealing plates are machined from aluminum or other metals or any suitable plastic, for example, about 0.75 inch thick polypropylene with upper 5552 and lower 5554 faces. Sealing plates constructed according to the present invention can be used as members being attached to conveyors to carry trays in the packaging system.

[0857] Referring now to FIGS. 168-171, one aspect of the sealing plates is to provide a method of stretching webs after being bonded to tray. Referring first to FIG. 168, package 5624 containing goods 5614 is shown with webs 5602 and 5604 stretched taut. In FIG. 168, the tray web 5600, first web 5602, and the second web 5604 are shown sealed together to form a complete package 5624. Referring now to FIG. 169 dotted lines 5618 are shown to represent the position of the side walls 5616 before insertion of the tray 5600 into the aperture 5606 in the sealing plate member 5608 shown in FIG. 170. Referring to FIG. 170, the aperture 5606 is located in plate member 5608 which in turn is attached to two chains 5605 on opposite sides thereof. The aperture 5606 has dimensions slightly smaller than the external dimensions of the side walls of the tray web 5600 such that when the tray 5600 is inserted into the aperture 5606, the side walls are urged inwardly.

[0858] Referring now to FIG. 171, dotted lines 5617 show the relative position of the edge of the flange 5610 that may be present prior to the tray insertion into the aperture 5606, whereas solid lines 5620 show the edge of flange 5610 after insertion of tray into aperture 5606. After bonding the tray to webs and release of the tray from the sealing plate, the tendency of flange to return to its original position urges webs taut, substantially retaining the position that is induced by placing the tray into the aperture 5606. In this manner, the webs are held taut to present a more attractive appearance for a potential buyer Referring again to FIG. 170, wherein a plan view of a section of a conveyor such as may be installed in a packaging machine, is shown. Sealing plate 5608 may have a plurality of apertures 5606, all of a suitable size and arranged to hold a plurality of the trays in a flexed condition as herein described.

[0859] Referring again to FIG. 169, the arrangement of tray web 5600 (tray) with a flange 5610 extending continuously around the perimeter of tray 5600 to provide a flat ledge to which first web 5602 can be sealed, is shown. Tray 5600 has been distorted such that side walls are urged inwardly and held in position by the limiting size of aperture 5606 located in sealing plate 5608 of FIG. 170.

[0860] Referring again to FIG. 168, in one instance, first web 5602 is a gas permeable material such as pPVC of about 0.0008 inches thick and tray web 5600 is constructed of a substantially gas impermeable material such as a co-extruded multilayer sheet of Eastobond APET 9921 and a blend of about 16% Eastobond PETG 6763 and about 84% Eastobond 9921. A second web 5604 is sealed to first web 5602 adjacent to seal 5612 of the first web to the tray web. Alternatively, the tray 5600 can be formed from a web of polystyrene foam that has been previously laminated to a web of gas barrier material. A first web of material can be sealed to the web of gas impermeable material laminated to the upper side (inside) of foam tray. Trays according to the present invention are substantially impermeable to gases. Webs are shown sealed together by a strip-like seal 5612 on flange 5610 that follows a path that continues around the flange near the perimeter of the package thereby providing a substantially hermetically sealed package. Goods 5614 are contained within the sealed package and a suitable gas blend which may include about 40% carbon dioxide and about 60% nitrogen is provided within the package. Sealing of the package is effected while side walls 5616 of the tray 5600 are urged inwardly. Side walls 5616 thereby retain a tension and desire to return to their original relative position thereby exerting a substantially outwardly disposed urging around the perimeter of the depression in the tray 5600 but which is retained and held captive by the combined strength of second and first webs sealed to the flange. Second web 5604 can be sealed to the package in such a manner as to allow peeling from the package, without rupturing first web and thereby leaving first web attached to the flange. When second web is peeled from the package the strength of the first web 5602 is sufficient to restrain outwardly urging of the side walls, thereby providing a means to stretch the first web 5602 into a substantially flat condition. The extent of the urging can be controlled such that it will maintain a tension in first web 5602.

[0861] 3.6.2. Overwrapping and Web Stretching

3.6.2.1. Embodiment

[0862] Controlled Atmosphere Packages (CAP) are packages prepared or treated in an oxygen deficient atmosphere to remove or prevent the accumulation of oxygen within the package materials. Packages are overwrapped with apparatus having web stretching capabilities in an enclosed conduit containing a suitable has as herein above described.

[0863] Referring now to FIG. 172, a section of PVC web material 5700 used for overwrapping is illustrated. Web material 5700 is about 0.0008″ in thickness. However, any suitable thickness or gauge can be used. Web 5700 can be coated, fully or in part and with any desired pattern such that parts of the web remain clear and other coated parts may be opaque. Web 5700 is shown with a suitable heat sealing coating that has been applied in two continuous strips 5704 along the edges of the web such that a continuous, central strip 5702 remains clear. The width of the clear section central strip 5702 may be about 50% of the total width of the web 5700 and the outer two printed sections 5704 of about equal width being about 25% of the full width each of web 5700.

[0864] Referring to FIG. 173, web 5700 may be formed into a tube when folded along a lateral axis, such that edges of portions 5704 may be joined such that when formed into a tube 5714, a fin seal, 5708, can be provided by heat sealing the edges. In one instance, the sealed tube, can include an upper clear section through which a tray 5710 and its contents can be seen and a lower, opaque section 5712 through which a tray 5710 and its contents cannot be seen.

[0865] Referring now to FIG. 173, web 5700 can be processed by a modified Hayssen machine model RT1800, for example, in such a manner so as to form a continuous tube 5714, where PVC web material forms a “fin” sealed tube, such that fin 5708 is formed on a lower surface of tube 5714. Suitable packaging trays 5710, such as Mono-Pak™ or any other tray herein described, that have been filled with perishable goods such as ground beef can be inserted into the tube 5714, by automatic devices (not shown) or any other suitable devices, and lateral stretching can be induced into the tube 5714. The lateral stretching can cause the tube 5714 material to firmly contact the tray 5710 and hold the perishable goods contained therein firmly. After the trays 5710 are located inside, the fin sealed tube 5714 can also be stretched longitudinally. After the longitudinal stretching of the tube 5714, lateral fin seals also may be formed, followed by severing of the tube 5714 adjacent to the lateral fin seals, can be provided so as to provide a fully and hermetically sealed package as shown in FIG. 174. The lateral and longitudinal stretching can be provided prior to sealing and severing of the lateral fin seals. Longitudinal stretching can be effected by the modified Hayssen model RT1800 after modification as generally described below.

[0866] The following disclosure details the modification that can be incorporated in the RT1800 so as to facilitate the use of pPVC web material as the over wrapping packaging material used thereon to over wrap such packages as the Mono-Pak EPS, or any other tray, foam or otherwise.

[0867] The Hayssen RT1800 is manufactured by Hayssen, a division of the Barry-Wehmiller Company, which is located at 225 Spartangreen, Boulevard, Duncan, S.C. 29334. Other information describing the RT1800 can be obtained from the following Web site: www.hayssen.com. The RT 1800 incorporates a “rotary die wheel” in such a manner so as to provide a continuous movement of the web during machine operation and package sealing. This arrangement provides a method to process and seal packages more rapidly than other types of over wrapping machines but until now, the RT 1800 has not been used to over wrap packages with pPVC (plasticized polyvinylchloride) web material.

[0868] It is desirable to use pPVC web material, in this particular application, because of its most suitable physical characteristics for the packaging of fresh meats such as ground meats and poultry pieces. However, the standard RT1800 is not ideally suited to process pPVC web material and in order to ensure efficient stretching and sealing of the pPVC web, the modifications to the RT1800 are necessary.

[0869] The HAYSSEN RT1800 rotary die wheel concept operates on the principal of maximizing dwell time. Individual MAGNUM sealing dies are released on demand as packaging material and product move through the machine. The RT1800 packaging equipment is well known to those skilled in the arts and all details of the RT 1800 machine construction are readily available from the manufacturer to potential end users of this popular packaging equipment.

[0870] Suitable packaging materials for use in this aspect of the invention, may include the Mono-Pak™ EPS tray, over wrapped with plasticized PVC web material, (supplied by AEP/Borden or Huntsman).

[0871] It should be noted that the readily available, low cost, pPVC web material as intended for use in this application, has the following properties:

• • [0872] 1. Glass clarity
  • [0873] 2. Stretch and high extensibility (50-100% before exceeding elastic limit)
  • [0874] 4. Memory, providing a “return to its original condition” after stretching (within elastic limit).
  • [0875] 5. Standard, enhanced oxygen permeability.
  • [0876] 6. Rapid heat sealing to itself.
  • [0877] 7. Rapid hot “knife” cutting, providing clean cut edges.

[0878] Generally, the basic RT1800 machine, as manufactured by Hayssen, would remain similar to existing standard equipment, except for the modification described herein. The existing longitudinal fin or lap sealing may require adjustment to facilitate an enhanced lateral web “stretching” capability for a pPVC web. The longitudinal web stretching apparatus, as disclosed herein, should be capable of installation without major structural and basic frame modifications to the existing equipment.

[0879] Referring now to FIG. 175, the apparatus constructed according to the present invention includes a die wheel 5716 shown in part with the axis of the wheel marked as axis 5718. A number of die carriers 5720 are also shown connected to the axis 5718. For the most part, the wheel die assembly includes a standard Hayssen component modified according to the present invention.

[0880] The packaged product 5754 may include any of the number of trays disclosed herein, over wrapped with standard (with enhanced O₂ permeability) plasticized PVC web material, (supplied by AEP/Borden or Huntsman). In one aspect, the tray EPS material can be produced with a surface finish that will not “cling” to the pPVC web material.

[0881] Plasticized web of stretch over wrap material is printed or plain material can be used. Partial coating of the inside web surface, with a low melt heat activated coating (HAC), can provide improved performance.

[0882] Referring now to FIG. 176, a detailed portion of the modification according to the present invention is shown. A first and second package (both denoted by reference numeral 5754) are shown enclosed in a tube of web material 5700. Web material 5700 is seen being clamped on the bottom and top sides thereof by an assembly designed to stretch, seal and cut web material 5700. A full width, lateral, impulse, heat sealing, element 5732 (e.g., cut from Inconnel, SS sheet or other “marine” grade, SS sheet material) is installed by attachment to a horizontally disposed rigid and suitably heat tolerant, non metallic base 5760. Compensation for normal expansion and contraction of the element 5732, during heating and cooling, can be provided. The element 5732 is covered with suitable material (such as PTFE) so as to provide a “non-stick” surface that will not “cling” to pPVC web. The heating and sealing element 5732 is in close, adjacent and parallel disposition to a full length strip of a portion of the outer surface of roller 5724, as shown in the sketch. When held together under suitable pressure with two webs of pPVC material located between element 5732 and roller 5724, a full length and hermetic seal between the two webs can be produced.

[0883] The heat sealing device may include a heat bank. Use of either impulse or heat bank devices may be determined by manufacturer preference. In the case of a heat bank device, the clamping bars 5739 and 5730 would be separated and insulated from the adjacent heating elements 5732 and 5741 and the clamping bars 5739 and 5730 would require independent, return spring mounting. A suitable distance or gap (to insulate and control the sealing/cutting devices), between the top surfaces of the clamping bars (5739 and 5730) and the top contact surface of the heat elements 5732 and 5741 would be required. This would allow clamping of the web(s) by the clamping bars 5739 and 5714 with subsequent web clamping, sealing and cutting by the heat elements 5732 and 5741. Rubber coated roller 5724 with cam/clutch bearing includes a heat resistant rubber coated and suitably ground, solid steel, hardened, rigid roller. Roller 5724 is located between two end plates and mounted thereto by bearing (one located at each end of the roller 5724′. The bearings are of identical dimensions with the “cam/clutch” feature suitably provided in only one bearing. Such arrangement allows the roller 5724 to rotate in a clockwise direction only as shown by the arrow in the sketch.

[0884] Heat sealing element 5732 is arranged to mirror image element 5741 and web clamping bar 5730 is arranged to mirror image web clamping bar 5739.

[0885] Rubber coated roller 5744 with cam/clutch bearing includes a heat resistant rubber coated, solid steel, hardened, rigid roller identical to roller 5724 but with a “cam/clutch” feature provided in one only bearing so as to allow roller 5744 to rotate in a counter clockwise direction only, as shown by an arrow in the sketch. The surface finish on both rollers 5744 and 5724 can be arranged so as to cling to web 5700 when contact occurs between suitably tensioned web 5700.

[0886] Two end plates ______ and ______ are arranged to rigidly retain rollers 5744 and 5724 in relative, respective, parallel and separated proximity, allowing the rollers to rotate as described above. Both end plates may be fitted with suitable coil or flat return springs to hold the rollers 5744 and 5724 in a normal position at a desired distance from bars 5730 and 5739 and heating elements 5732 and 5741.

[0887] A cam follower is mounted to each end plate so as to engage with cam tracks (not shown but mounted to main frame of FFS machine) arranged to provide a web sealing pressure to web 5700 by causing depression of end plate return springs.

[0888] The web stretching bar 5726 includes a strip of suitable material suitably profiled that may be provided with an outer surface treatment that can cling to pPVC web material. Web stretching bar 5726 is attached to at least one pneumatic cylinder (5746) that may include slotted fixture apertures to eliminate locking that may otherwise occur during operation. The web-stretching bar is shown in a withdrawn (closed) position and also in a fully extended position, by dotted lines. When in the closed position, the upper and highest edge of the bar extends along its full vertical length (the vertical length is orthogonal to the cross section in FIG. 176 and cannot be seen) and is in contact with web 5700. This contact is arranged so as to ensure a suitable tension is induced in the web 5700. The contact between bar 5726 and the web 5700 urges the web 5700 upward toward the rollers 5724 and 5744. The rotation of the rollers 5724 and 5744 urges the web toward the bar 5726. The cam/clutches installed in the rollers will not allow the web to be pulled away from the web-stretching bar. Web 5700 can be freely stretched but is essentially clamped by its tensioned and intimate contact with the surface of the rollers (5724 and 5744) and the upper edge of the web-stretching bar 5726.

[0889] The roller assembly, includes two sets of rollers, 6244 and 6224, endplates, cam followers, fasteners and return springs as required. When assembled the complete web stretching assembly in a normally closed position maintains a suitable gap between the rollers and the adjacent contact surfaces of items 5730 and 5732, thereby allowing free stretching of the web 5700, by activation of web-stretching bar 7526.

[0890] A pneumatic cylinder 5746 is shown, attached to the web-stretching bar 5726 to extend bar 5726 to the position shown by dotted lines and thereby stretch the web 5700. In one aspect, two cylinders would be provided. Compressed air flow and pressure controls can be arranged to activate cylinders so as to optimize induced tension in web 5700. Any suitable alternative method of web-stretching bar activation and control may be used.

[0891] A vacuum tube 5737 may be conveniently located so as to provide a method of removing scrap web material, for example, any excess material accumulation may be directed to a canister.

[0892] It may be desirable to mount each roller and clamping assembly on an independent pivotal mount. A roller and clamping assembly refers to roller 5724, clamp bar 5730 and heating element 5732 as one assembly and roller 5744, clamp bar 5739, and heating element 5741 as a second assembly. Each roller and clamping is generally held in a central position where the roller and clamping assemblies are in close proximity to one another by controlled return springs. Activation of the web-stretching bar 5726 may cause the two assemblies to move away from one another until each assembly contacts a package 5754. The roller and clamping assembly including roller 5724 will contact the package 5724 shown on the right side of FIG. 176 (i.e., the completed package) while the roller and clamping assembly including roller 5744 will contact the package 5754 shown on the left side of FIG. 176. Such an arrangement will provide consistent web stretching and a final web heat seal at a constant distance from the package. In this configuration, end plates would require slotting to accommodate outward movement of each roller and clamping assembly.

[0893] During operation the following events may occur. The packages 5754 move along a conveyor (not shown) until one is positioned on either side of the roller/clamping assemblies as shown in FIG. 176. Then pneumatic cylinders move the base 5760 forward toward the web 5700 located in the gap between the packages 5754. At this point, several options exist. In one embodiment, the clamp 5739 clamps the web 5700 against the roller 5744 tightly. However, the web is not clamped against roller 5724 by clamp 5730. Then the web stretching bar 5726 moves forward and stretched the web. In this manner, the web portion surrounding the package 5754 located on the side rear roller 5724 is stretched. Then the clamp 5730 is moved forward to clamp the web 5700 to the roller 5724. Next the heating elements 5732 and 5741 move forward and seal the web 5700 at points of contact between the heating elements and the web 5700. The heating may sever the web or cutters (not shown) may be included to sever the web 5700. The scrap portion of the web 5700 (i.e., the portion located between inside surfaces of heating elements 5732 and 5741) may be removed by vacuum tube 5737. Then the roller/clamping assemblies are retracted (moved out from between the packages 5754) and the conveyor indexes the left package to the right and a new package into the position previously occupied by the left package. The above cycle then repeats for each successive set of packages.

[0894] In another embodiment, after the pneumatic cylinders move the base 5760 forward toward the web 5700, the clamp 5739 does not clamp the web 5700 against roller 5744. Instead, the clamps 5739 and 5730 urge the web against the rollers 5744 and 5724 but do not clamp the web to the rollers. Then the web stretching bar 5726 moves forward as each roller and clamp assembly moves outward (i.e., toward the packages located on their respective sides of the web stretching bar 5726). After the roller and clamp assemblies have been stopped from further outward movement by contact with the packages 5754 and the web stretching bar 5726 has completed its forward movement, the clamps (5730 and 5739) and the heat sealing elements (5732 and 5741) move forward and clamp the web 5700 to the rollers (5724 and 5744). The heating elements then seal the web in the locations where the heating elements are in direct contact with the web 5700. Then the cycle completes in a similar manner to the cycle described above. The scrap web material is removed and the roller and clamping assemblies are withdrawn. Then the conveyor moves or indexes the package (as described above) and the cycle repeats.

[0895] Products, pre-filled with ground beef portions/blocks, are automatically loaded onto the entry end of the Hayssen FFS equipment. Orientation of the products may be in normal or inverted disposition. A normal disposition (with package “open top” side facing upward) would require a side fin or lap web seal, whereas an inverted disposition would require a bottom web seal. Normal operation would include longitudinal sealing after induction of maximum stretch in web 5700. Lateral sealing would occur after longitudinal stretching by web stretching bar 5726. Activation of the web-stretching bar would not commence until closure of the subsequent closing of the closest clamp to the rear portion of wheel. In this way, gradual stretching of the pPVC over wrap, during the wheel rotation, can occur until the desired level of stretch and/or tension is achieved when web heat sealing and simultaneous cutting could be provided immediately prior to ejection of the finished package(s). The finished packages could be ejected in a normal and upright disposition, assuming that the packages were loaded in an inverted disposition, alternatively, the packages could be inverted after ejection if the packaging had been loaded onto the RT1800 packaging machine in a normally upright position.

[0896] By incorporating the above described modification in the Hayssen RT 1800 packaging machine a web stretching arrangement is provided to stretch the over wrap material 5700 during the normal rotation of the die wheel. It is anticipated that, in view of the rapid heat sealing and cooling characteristics of thin gauge (0.0008″) pPVC, the operational speed of the Hayssen RT 1800 could be increased to more than 1800 feet per minute.

3.6.2.2. Embodiment

[0897] Referring now to FIG. 177, a cross section through an assembly substantially similar to the device described in association with FIG. 176 herein above is shown but having some differences as described below. A base 5812 is attached to profiled bar 5819 with upper assembly, comprising rollers 5860 and 5865 retained by bar 5820 in clamping position. Two package trays 5867 and 5861 are shown with clamped assembly there between. Heat seal bar 5818 and clamp 5817 assembly is mounted to a pneumatic piston and cylinder 5863 with web 5810 stretched there across and tensioned with web section 5868 stretched over roller 5865. An aperture 5869 is provided in web section 5810 and an enclosed space 5821 is contained within the assembly and substantially sealed and separated from the surrounding atmosphere 5822. A port 5862 is provided in profiled bar 5819 and in communication with space 5821. A vacuum applied to port 5862 can therefore lower the pressure in space 5821 which is in direct communication with space 5823 through aperture 5869. In this way, gas in space 5823 can be extracted thus lowering gas pressure in the space and causing web 5868 and 5810 to collapse toward the tray 5861 and therefore by controlling the level of vacuum applied to space 5821 through port 5862 the amount of gas in space 5823 can be adjusted to any desired level prior to sealing web section 5868 to web section 5810 at a strip along the roller 5865 and bar 5863. In this way, the web section 5868 can be sealed to web section 5810 after the gas pressure in space 5823 has been adjusted to a desired level.

3.6.2.3. Embodiment

[0898] Referring now to FIG. 178, a schematic, side elevation view of a web stretching and sealing sub-assembly, that can be installed into a horizontal, form, fill and seal packaging machine, such as an Integra Flowpak, is shown. A continuously formed tube 5902 of stretch material is provided in a horizontal disposition with loaded trays such as 5900 and 5901 enclosed therein. Tube 5902 may be formed by lap or fin sealing together the edges of a flat web of material such as pPVC or a suitable stretch PE web of material and with a thickness of less than about 0.001″. Conveyors 5903 and 5904 carry tube 5902 in the direction shown by arrows 5935 and 5936. A space 5937 is, provided between the ends of conveyors 5903 and 5904 to allow lower sealing assembly 5906 to be elevated there between and to mate, as required with upper sealing assembly 5905 that can be lowered accordingly and as required to mate with the opposing lower assembly 5906. Assembly 5906 is arranged with two outer clamping bars 5907 and 5915 that are in line and adjacent to correspondingly opposing clamping bars 5907 and 5915 attached to assembly 5905. All clamping bars 5907, 5915, 5908 and 5916 are mounted in such a manner that they can be independently activated by moving means such as pneumatic cylinders or other suitable drives, in a vertical reciprocating action and thereby clamp web 5902 as required between the corresponding opposing clamps. Heat banks 5909 and 5913 are mounted on assembly 5906 with independent driving means, such as pneumatic cylinders or other suitable drives. Two rollers 5918 and 5919 can be mounted to lower assembly 5906, via cam clutch bearings such that roller 5918 can rotate in a clockwise direction only as shown, by arrow 5938 and roller 5919 can rotate in a counter clockwise direction only as shown by arrow 4939. A vacuum tube 5912 is mounted to lower assembly 5906 and is arranged to provide a means of removing excess web material that is severed from the web 5902 during operation of the apparatus. Heat banks 5910 and 5914 are mounted to assembly 5905 in such a manner as to correspondingly oppose heat banks 5909 and 5913 respectively on assembly 5906, and in such a manner that sides of web tube 5902 can be sealed together along a traverse sealing strip, at the contact point between heat bank 5909 and 5910 and heat bank 5914 and 5913. The sealing strip in tube 5902 provided by each correspondingly opposing set of heat banks can be arranged to completely seal across the full width of the tube 5902 in a hermetically or liquid tight manner. A web stretching bar 5911 is mounted centrally to upper assembly 5905 and is attached to a driving mechanism that can independently extend and retract the stretching bar 5911 in a vertical reciprocating motion, as required. Lateral knives 5940 and 5941 can be mounted as shown and independently activated by driving mechanisms so as to provide a web cutting feature as may be required.

[0899] Referring now to FIG. 179, upper assembly 5905 has been lowered between packages 5900 and 5901 and lower assembly 5906 has been elevated so as to compress tube 5902 in a clamping motion. In one aspect, packages may be concaved at an end that is to receive compressive forces. Referring now to FIG. 180, upper assembly 5905 and lower assembly 5906 are closed and clamps 5907 and 5908 are firmly clamping web 5902 in such a manner so as to hold it firmly and stationary. Opposing clamps 5915 and 5916, however, have been closed toward each other so as to depress walls of web 5902 toward each other but not to contact and clamp together. Web stretching bar 5911 has been activated so as to stretch the central portion of web 5902 and in this way tension is induced into the web section, therefore pulling web 5902 from between the point of clamping by clamps 5907 and 5908 to the seal 5917, located at an opposite end of package 5901. In this manner, the web tube 5902 is stretched laterally from the seal 5917 around package 5901. Clamps 5915 and 5916 react against the tendency of tray 5901 to be drawn toward the stretching bar 5911, holding it firmly against the stretching action of bar 5911 and in this way, web 5902 can be stretched. Referring now to FIG. 181, correspondingly opposing clamps 5907 and 5908 are held closed and correspondingly opposing clamps 5915 and 5916 are also held closed so as to firmly clamp web 5902 there between. Similarly correspondingly opposing heat banks 5910 and 5909 are closed and correspondingly opposing heat banks 5913 and 5914 are also closed so as to heat seal web 5902 along strip seals between each pair of heat banks. At this time, web 5902 will be severed along the outer edges of both seal strips which are closest to the stretch bar 5911 at 5991 and 5993. A vacuum source, attached to tube 5902 can be applied to remove scrap section 5992. Referring now to FIG. 182, it can be seen that the opposing assemblies 5905 and 5906 have been retracted away from each other and finished package 5901 has been sealed at 5993. It can be seen that a mechanical stretching of web 5902 can be provided without the need to use the more expensive method of heat shrinking a costly heat shrinkable web material.