Method and System for Treating Food Items with an Additive and Solid Carbon Dioxide

Abstract

Embodiments of the invention generally provide methods and systems that distribute an additive in solid carbon dioxide in an interior of food processing equipment. The additive may be injected into a flow of liquid carbon dioxide upstream of an expander at or adjacent to the interior. Injection of the additive into the interior may be alternated with directing a flow of expanded carbon dioxide into the interior. In some embodiments, the freezing point of the additive with or without a diluent composition and/or additive(s) is lower than a temperature of the liquid carbon dioxide.

What is claimed is: 
     
         1 . A method of treating a food item comprising the steps of:
 providing a flow of liquid carbon dioxide to an interior of food processing equipment;   expanding the liquid carbon dioxide at or adjacent to the interior to form a flow of gaseous and solid carbon dioxide thereat;   directing the flow of gaseous and solid carbon dioxide into the interior to come into contact with food items therein; and   injecting a flow of an additive into the interior before, during or after directing the flow of gaseous an solid carbon dioxide into the interior.   
     
     
         2 . The method of  claim 1 , wherein:
 the additive is injected into the flow of liquid carbon dioxide;   the liquid carbon dioxide and additive are mixed in a conduit; and   the mixed additive and liquid carbon dioxide are expanded at or adjacent the interior to cause the additive and the gaseous and solid carbon dioxide to contact the food items.   
     
     
         3 . The method of  claim 2 , wherein said expansion is performed with a snow horn adjacent the interior; and
 a flow of the expanded additive and carbon dioxide are directed from the snow horn into the interior to contact the food items.   
     
     
         4 . The method of  claim 2 , wherein the mixed additive and liquid carbon dioxide are expanded at a nozzle fluidly communicating with the interior. 
     
     
         5 . The method of  claim 1 , wherein said step of injecting the additive is repeatedly alternated with said step of directing the flow of gaseous and solidified carbon dioxide. 
     
     
         6 . The method of  claim 5 , further comprising the steps of:
 providing a tank of liquid carbon dioxide having a headspace of gaseous carbon dioxide;   providing a container of the additive;   providing a first conduit fluidly communicating with the container;   providing a second conduit fluidly communicating with the liquid carbon dioxide in the tank, the first conduit, and the interior of the food processing equipment;   causing a pressure in an interior of the container to be higher than a pressure of the flow of liquid carbon dioxide; and   alternatingly allowing the liquid carbon dioxide to flow through the second conduit to the food processing equipment interior and allowing the additive to flow through the first and second conduits to the food processing equipment interior.   
     
     
         7 . The method of  claim 6 , wherein said step of causing a pressure comprises:
 pressurizing the container interior with the gaseous carbon dioxide in the tank headspace;   providing a liquid carbon dioxide regulator in fluid communication between the tank and the second conduit; and   reducing a pressure of the liquid carbon dioxide flowing into the second conduit with the regulator such that the flow of liquid carbon dioxide has a pressure lower than that of the tank.   
     
     
         8 . The method of  claim 6 , wherein said step of causing a pressure comprises pressurizing the container interior with an external source of gaseous carbon dioxide to a pressure higher than that of the tank headspace. 
     
     
         9 . The method of  claim 1 , wherein the additive is diluted in a diluent composition and the diluted additive/diluent composition has a freezing point lower than a temperature of the liquid carbon dioxide. 
     
     
         10 . The method of  claim 9 , wherein the diluent composition comprises a non-aqueous solvent. 
     
     
         11 . The method of  claim 10 , wherein the diluent composition further comprises water. 
     
     
         12 . The method of  claim 4 , wherein the food processing equipment is selected from the group consisting of: bottom injection mixers; top injection mixers; CO 2  refrigerated cabinet freezers; CO 2  refrigerated tunnels; CO 2  refrigerated spiral tunnels; blenders; marinators; meat choppers; vegetable choppers; auger screws; food transport containers; batch tumblers; and continuous tumblers. 
     
     
         13 . The method of  claim 12 , wherein the food processing equipment is a bottom or top injection mixer and said method further comprises the step of mixing the food product in the food processing equipment interior with the solid carbon dioxide and the additive. 
     
     
         14 . The method of  claim 13 , wherein the food item is meat. 
     
     
         15 . The method of  claim 2 , further comprising the steps of:
 providing a tank containing the liquid carbon dioxide;   providing a container of the additive; and   providing a liquid pump, wherein the additive is injected into the flow of liquid carbon dioxide with the pump.   
     
     
         16 . The method of  claim 1 , wherein the additive is not dissolved in a solvent and has a freezing point lower than a temperature of the liquid carbon dioxide