BACTERIOLOGICAL STANDARDS FOR MILK 



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is not applicable. Thus, it can be ascertained microscopically 

 whether or not water has been added to the milk or if it is full 

 milk, half milk or skimmed milk. 



The bacteriological standardization of milk has received much 

 attention within recent years and all civilized countries have 

 adopted certain numerical limits of bacteria permissible in whole- 

 some milk. Unfortunately, however, there is very little uniformity 

 regarding these numerical limits in different countries or in differ- 

 ent parts of the same country. In some cities and communities 



Fig. 38. — Milk fat globules very highly magnified (X 1000). A group of lactic 

 acid bacteria at the left. — (Hunter.) 



there are two standards, a summer or low (numerical limit higher) 

 standard and a winter or high (numerical limit lower) standard. 

 The terms summer and winter are, however, misleading in certain 

 areas of the United States and, for regulatory purposes, it would be 

 better to base the standards on a temperature differential, irre- 

 spective of season, combining this with a sliding scale of bacterial 

 count. Under such a plan the Southern States, including the 

 immediate Pacific Coast region, would be under a single standard, 

 namely, the lower or so-called summer standard. The rest of the 

 United States would have both standards. 



