DAIRYING 



ing is in progress. The udder should be thoroughly 

 clean, and the milking should be done with dry hands. 

 The milk coming from a healthy. cow is pure, but, if it is 

 kept in a dirty stable or in a milk room where the air is 

 not pure, it soon absorbs the foul odors and becomes 

 tainted. 



Bacteria. There are many bacteria that get into the 

 warm milk, and multiply so rapidly that the milk sours. 

 To avoid the bacteria, the utmost cleanliness must be ob- 



FIG. 116. Microscopic appearance of ordinary milk showing fat globules and bacteria in 

 the milk serum. The cluster of bacteria on left side are lactic-acid-forming germs. (H. L. 

 Russell, Wis. Bui. No. 62.) 



served in the stables, in milking and in the milk room. 

 It will be impossible even then to avoid them altogether, 

 but their number will be greatly reduced. Cooling the 

 milk as soon as possible after it is drawn prevents the 

 bacteria from multiplying, and makes it possible to keep 

 the milk sweet. 



