Decontamination methods for meat using carbonic acid at high pressures

Abstract

A method for separating lean meat from lean meat-containing material includes combining a particulate material with fluid, subcritical carbon dioxide at a pH of about 7 or less and a pressure of about 600 psig. The material and fluid is introduced into the vessel and is separated into low density and high density fractions. The material from the low density fraction is removed via an outlet and has a higher percentage of fat than the material introduced into the vessel. The material from the high density fraction is removed via an outlet and has a higher percentage of lean meat than the material introduced into the vessel. The vessel can include a centrifuge or a vessel disposed toward the vertical having an upper and lower outlet, wherein the separation is achieved by the respective densities of the material, and the natural or an artificial gravity field.

1 . A method for separating lean meat from lean meat-containing
 material comprising:   combining a particulate material having lean meat and fat with a fluid comprising subcritical carbon dioxide, wherein the combination of the material with the fluid has a pH of about 7 or less;   introducing the material and fluid into a vessel to fill the vessel, wherein the vessel has first and second outlets, and allowing the material to separate into low density and high density fractions within sections of the vessel;   removing material from the low density fraction via the first outlet of the vessel, wherein the material removed from the first outlet has a higher percentage of fat than the material introduced into the vessel; and   removing material from the high density fraction via the second outlet of the vessel, wherein the material removed from the second outlet has a higher percentage of lean meat than the material introduced into the vessel.   
   
   
       2 . The method of  claim 1 , wherein the density of the fluid is adjusted by the addition of water. 
   
   
       3 . The method of  claim 1 , wherein the density of the fluid is increased by the addition of water and sodium chloride. 
   
   
       4 . The method of  claim 1 , further comprising grinding the material prior to combining with the fluid. 
   
   
       5 . The method of  claim 1 , further comprising adjusting the temperature of the material prior to combining with the fluid to a temperature of about 28° F. to about 109° F. and adjusting the pressure to lower than 600 psig. 
   
   
       6 . The method of  claim 1 , further comprising:
 extracting the material removed from the low density fraction of the first vessel;   introducing the extracted material into a second vessel having a first outlet and a second outlet;   allowing the material to separate into low density and high density fractions within sections of the second vessel;   removing material from the low density fraction via the first outlet of the second vessel, wherein the material removed from the first outlet has a higher percentage of fat than the material introduced into the second vessel; and   removing material from the high density fraction via the second outlet of the second vessel, wherein the material removed from the second outlet has a higher percentage of lean meat than the material introduced into the second vessel.   
   
   
       7 . The method of  claim 1 , further comprising separating fluid from the low density fraction. 
   
   
       8 . The method of  claim 1 , further comprising separating fluid from the high density fraction. 
   
   
       9 . The method of  claim 1 , wherein the vessel comprises an inlet at about the midsection of the vessel, and the material and fluid are introduced at the inlet at about the midsection of the vessel. 
   
   
       10 . The method of  claim 1 , further comprising separating fluid from the material in the low density fraction, separating fluid from the material in the high density fraction, and recycling the separated fluid to combine with material. 
   
   
       11 . The method of  claim 1 , further comprising processing material having lean meat and fat in a centrifuge. 
   
   
       12 . The method of  claim 1 , further comprising measuring the carbon dioxide combined with the material to maintain a ratio of about one-half to four times the flow rate of the material. 
   
   
       13 . The method of  claim 1 , further comprising removing fluid from the vessel that is about equal to the amount of fluid that is combined with the material. 
   
   
       14 . The method of  claim 1 , further comprising introducing an agent from at least one of sodium chloride, sodium chlorite, carbon monoxide and sodium citrate. 
   
   
       15 . The method of  claim 1 , wherein the material removed from the high density fraction is identified with one or more animals from which material originated. 
   
   
       16 . A method for separating fat from material containing lean meat and fat, comprising:
 introducing a material containing lean meat and fat to a conduit containing a rotating and tapering transfer mechanism;   introducing carbon dioxide to the conduit at a pressure and temperature below the critical temperature and critical pressure for carbon dioxide;   transferring the material and carbon dioxide along the conduit by rotating the tapering transfer mechanism; and   separating carbon dioxide with fat through an outlet disposed along the conduit to produce material product containing a lower percentage of fat than the material introduced into the conduit.   
   
   
       17 . The method of  claim 16 , further comprising measuring the fat and moisture content of the material prior to introducing to the conduit, and optionally introducing carbon dioxide at a controlled pressure and a measured proportion of water to adjust the moisture content of the material. 
   
   
       18 . The method of  claim 16 , further comprising introducing an agent from at least one of sodium chloride, sodium chlorite, carbon monoxide and sodium citrate. 
   
   
       19 . The method of  claim 16 , wherein the material product is identified with one or more source animals from which material originated. 
   
   
       20 . The method of  claim 19  wherein the identification of at least one source animal is attached to the meat after processing.