Method and System for Producing a Soft Food Product

The invention relates to a novel method and apparatus for producing a soft food mixture, such as soft ice cream.

Vast quantities of soft ice cream and similar products are consumed each year in the United States. Soft ice cream is a product which is similar in its constituents to normal ice cream but which is produced in a fashion such that the product has a much softer consistency than that of normal ice cream. This product has been but is not usually mixed with nitrous oxide (N.sub.2 O) and/or Freon and dispensed from a cooled cylinder directly into the cone or cup in which it is sold.

One technique employed in the past for adding nitrous oxide to a food mix involves injecting the nitrous oxide into a moving mix stream. The difficulty with this technique is that the nitrous oxide may not be uniformly and completely mixed with the material. There are simply too many variables for this technique to be completely satisfactory.

The present invention relates to a unique apparatus and method whereby a food mix, for example, the constituents making up soft ice cream, is atomized and injected into a saturation tower. A source of nitrous oxide and a food grade fluorocarbon such as Freon (Trademark) above atmospheric pressure is also coupled to the tower so that the atomized mix is completely and uniformly combined with the gases. The more nitrous oxide which goes into solution, the better the consistency of the product. In order to make sure that the final product has uniform consistency, the mix which settles to the bottom of the tower, which is combined with the gases, is continuously pumped to a location at the top of the tower where it is injected against a barrier plate to form particles which fall through the nitrous oxide and fluorocarbon gases to resettle on the bottom. At the same time, the mix is drawn off the bottom of the tower and pumped to a conventional filler device. Recirculating the mix produces a much more uniform composition than would be otherwise produced.

Preferably sensors are provided in the tower for controlling the pump which supplies mix to the tower to maintain the level of saturated mix in the tower within predetermined limits. This is desirable to maintain the pressure in the tower within a relatively constant range. A heat exchanger is also preferably included between the pump and the atomizer for removing any heat added to the mixture by the pump. Such heat is generally deleterious to the solubility of the gases in the mix. A further sensor is also provided for sensing when the mixture in the tower drops below a predetermined level and coupled to a valve between the output line and the pump which delivers the saturated fluid to the conventional filler to cut off delivery when the sensed level falls below a predetermined level.

Many other aspects of the invention will be clear from the following detailed description of the drawings.

The FIGURE shows a schematic view of the unique system and method of this invention.

Reference is now made to the FIGURE which schematically illustrates one embodiment of the unique apparatus and method of this application. A food product such as a soft ice cream mix, yogurt, or other similar material, is pumped from a storage tank 20 by a conventional pump 22 through check valve 24 and injected into saturation tower 26 via conventional atomizing nozzle 28. A conventional heat exchanger 30 is disposed between nozzle 28 and pump 22 for removing any heat added to the mixture by pump 22.

A mixture of nitrous oxide (N.sub.2 O) and a food grade fluorocarbon such as Freon (Trademark) gas are similarly added to the cooling tower adjacent the top thereto at a pressure above atmospheric so that the atomized particles are mixed the N.sub.2 O and Freon as they fall to the bottom of the cooling tower and collect. The collected mixture in the bottom of tower 26 is recirculated by pump 32 and injected into tower 26 at the top thereof to impinge upon a baffle plate or barrier 35 to form particles which fall again to the bottom of tower 26. Recirculation of the fluid has been found to produce a much more uniform mix than the mix produced without such recirculation. A heat exchanger may also be desirable between pump 32 and the point of re-entry into tower 26.

Conventional sensors 36 and 40 are disposed near the desired level of saturated mix in tower 26 and provide suitable electrical signals for controlling pump 22 so as to control the amount of injected mix to maintain that level. It has been found that any variation from that level substantially changes the pressure within tower 26 which leads to undesirable changes in the consistency of the final product.

The saturated mix in tower 26 is drawn off at output line 41 by pump 42 and transferred to a conventional filler 44 which fills pressurized cans in a conventional manner. Filler 44 preferably includes an individual pressure control valve for each of the lines and a pressure gauge for monitoring the pressure at the filler. A heat exchanger may be desirable in the line between pump 42 and filler 44. Valve 46 is disposed between outlet line 41 and pump 42 and is controlled by a further conventional sensor 48 which provides an output signal closing valve 46 and stopping pump 42 whenever the level of saturated mix in saturation tower 26 drops below a desired level.

Many changes and modifications in the above described embodiment of the invention can, of course, be carried out without departing from the scope thereof. Accordingly that scope is intended to be limited only by the scope of the appended claims.