440 



MICROBIOLOGY OF MILK AND MILK PRODUCTS 



DIFFERENCE IN NUMBER OF BACTERIA IN MILK DRAWN BY MEN IN SAME STABLE 



THE UTENSILS. If properly cared for, the dairy utensils should 

 not add to the germ content of the milk. Not infrequently, however, 

 they are faulty in construction. In open seams and other places the 

 milk may accumulate and not be thoroughly washed out. Usually 

 when utensils of this sort are used, the methods for washing and ster- 

 ilizing are not sufficient and bacteria multiply in large numbers in the 

 cracks and crevices and contaminate each new lot of milk put into 

 them. Sometimes the utensils which are properly constructed may 

 contaminate the milk because they have not been properly cleansed 

 and sterilized. The possible effect of the utensils on the germ content 

 of the milk put into them is shown by recent work done at the Illinois 

 Agricultural Experiment Station.* It was found that when the uten- 

 sils were properly washed and thoroughly steamed and dried they did 

 not add many bacteria to the milk. On the other hand, when they 

 were not well steamed and especially when allowed to stand wet for 

 several hours they added very large numbers of bacteria to the milk. 

 This is shown by the following table. 



AVERAGE NUMBER OF BACTERIA ADDED TO FIFTY LITERS OF MILK BY THE VARIOUS 

 UNSTEAMED UTENSILS IN WHICH IT WAS HANDLED 



* Illinois Bull. 204, 1918. 



