Pasteurized in-shell chicken eggs and method for production thereof

Abstract

A method of pasteurizing in-shell chicken eggs by heating eggs until a central portion of the yolks of the eggs is at a temperature between 128° F. to 138.5° F. That temperature is maintained and controlled for times within parameter line A and parameter line B of FIG. 1 and sufficient that any Salmonella species present in the yolk is reduced by at least 5 logs but insufficient that an albumen functionality of the egg measured in Haugh units is substantially less than the albumen functionality of a corresponding unpasteurized in-shell egg.

What is claimed is:  
     
         1 . A method of pasteurizing an in-shell chicken egg, comprising heating the egg until a temperature of a central portion of a yolk of the egg is controlled within the range of 128° F. to 138.5° F. and maintaining that controlled yolk temperature for times within parameter line A and parameter line B of FIG. 1 and sufficient that a Salmonella species present in the egg yolk is reduced in amount by at least 5 logs but insufficient that an albumen functionality of the egg measured in Haugh units is substantially less than the albumen functionality of a corresponding unpasteurized in-shell chicken egg.  
     
     
         2 . The method of  claim 1 , wherein the egg is heated with a fluid heat transfer medium.  
     
     
         3 . The method of  claim 2 , wherein the medium is an aqueous medium.  
     
     
         4 . The method of  claim 3 , wherein the aqueous medium is liquid water.  
     
     
         5 . The method of  claim 4 , wherein the water contains a surface active agent.  
     
     
         6 . The method of  claim 4 , wherein at least one of the water and the egg is in motion relative to the other.  
     
     
         7 . The method of  claim 2 , wherein the medium is heated to temperatures of at least 128° F.  
     
     
         8 . The method of  claim 7 , wherein the medium is heated to temperatures of at least 128° F. and up to 142° F. and the central portion of the yolk is controlled at a temperature of at least 128° F.  
     
     
         9 . The method of  claim 8 , wherein the medium is heated to more than one temperature.  
     
     
         10 . The method of  claim 9 , wherein the medium is heated to a higher temperature of less than 142° F. and then cooled to a lower temperature greater than 128° F.  
     
     
         11 . The method of  claim 10 , wherein the higher temperature is between about 136° F. and 138° F. and the lower temperature is between about 131° F. and 135° F.  
     
     
         12 . The method of  claim 1 , wherein said times are within a 95% confidence interval for a straight line graph of temperature and the log of dwell time in minutes where one terminus of the line is at 128° F. for 215 minutes and the other terminus of the line is at 138.5° F. for 8.0 minutes.  
     
     
         13 . The method of  claim 1 , wherein the Salmonella species is  Salmonella enteritidis.    
     
     
         14 . The method of  claim 1 , wherein the albumen functionality is at least 60 Haugh units for Grade A eggs.  
     
     
         15 . The method of  claim 1 , wherein the Salmonella species is reduced throughout the yolk and albumen of the egg by at least 5 logs.  
     
     
         16 . The method of  claim 1 , wherein the pasteurized egg has an egg weight substantially the same as a corresponding unpasteurized egg.  
     
     
         17 . The method of  claim 16 , wherein the pasteurized egg has a yolk index and yolk strength substantially the same as a corresponding unpasteurized egg.  
     
     
         18 . The method of  claim 17 , wherein the pasteurized egg has an angel cake test and sponge cake test substantially the same as a corresponding unpasteurized egg.  
     
     
         19 . The method of  claim 18 , wherein the pasteurized egg has frying, scrambling and boiling characteristics substantially the same as a corresponding unpasteurized egg.  
     
     
         20 . The method of  claim 19 , wherein said characteristics are maintained in the pasteurized egg for up to 75 days storage at 41° F.  
     
     
         21 . A pasteurized in-shell chicken egg, comprising a pasteurized central portion of a yolk of the egg having at least a 5 log reduction in a Salmonella species present in the yolk in its unpasteurized form, said egg having an albumen functionality measured in Haugh units not substantially less than the albumen functionality of a corresponding unpasteurized in-shell egg.  
     
     
         22 . The egg of  claim 21 , wherein the Salmonella species is  Salmonella enteritidis.    
     
     
         23 . The egg of  claim 21 , wherein the albumen functionality is at least 60 Haugh units for a Grade A egg.  
     
     
         24 . The egg of  claim 21 , wherein the Salmonella species is reduced throughout the yolk and albumen of the egg by at least 5 logs.  
     
     
         25 . The egg of  claim 21 , wherein the pasteurized egg has an egg weight substantially the same as a corresponding unpasteurized egg.  
     
     
         26 . The egg of  claim 25 , wherein the pasteurized egg has a yolk index and yolk strength substantially the same as a corresponding unpasteurized egg.  
     
     
         27 . The egg of  claim 26 , wherein the pasteurized egg has an angel cake test and sponge cake test substantially the same as a corresponding unpasteurized egg.  
     
     
         28 . The egg of  claim 27 , wherein the pasteurized egg has frying, scrambling and boiling characteristics substantially the same as a corresponding unpasteurized egg.  
     
     
         29 . The egg of  claim 28 , wherein said characteristics are maintained in the pasteurized egg for up to 75 days storage at 410° F.