THE PASTEURIZATION OF MILK 



interfere with the cream line which will be dis- 

 cussed later. 



Another objection which customers urge against 

 pasteurized milk is that it has a distinctly 

 scorched or cooked taste. This is undoubtedly true 

 when the milk is heated to a high temperature, or 

 when an uneven temperature is maintained. If the 

 heating medium is kept at a point greatly above 

 the temperature to which the milk is to be raised, 

 the same effect is produced. On account of this 

 cooked taste it is evident that there is a commer- 

 cial objection to pasteurization where it is not 

 properly or carefully done. 



Moreover, when a low temperature of heating is 

 used, the enzymes are not much affected, while 

 they are destroyed when a high temperature is ap- 

 plied. Indeed, the Storch test, which is used to 

 determine whether skim milk has been heated to 

 165 or higher in compliance with the laws in this 

 regard, depends upon the non-action of the en- 

 zymes. These are destroyed by high heating. 

 This test is of little or no value in testing milk 

 pasteurized at low temperature. 



Since an even heating at comparatively low 

 temperatures and a holding for a long time secures 

 30 



