CARE OF MILK FOR CHEESE-MAKING 5 



more bacteria there will be. Bacteria and dirt always 

 go together in dairy matters. The relations of bac- 

 teria to milk are considered in greater detail in 

 Chapter XXII, p. 285. 



The most common sources of bacterial infection are 

 the following: (i) Unclean or unhealthy condition 

 of cows; (2) unclean condition of stables or places of 

 milking; (3) unclean condition of persons milking 

 cows; (4) unclean condition of utensils used; (5) 

 keeping milk in unclean surroundings, and especially 

 at temperatures above 60 F. after milking. 



Unclean condition of cows. The hair on cows 

 favors the accumulation of dirt and dust. The con- 

 dition is worse in proportion as cows are not regu- 

 larly and thoroughly cleaned. Dust particles and 

 hairs, laden with bacteria, are in position to drop into 

 the milk-pail. While the hairs and coarse chunks of 

 dirt may be removed from milk by straining, the 

 bacteria are, in large part, washed off into the milk 

 and cannot be removed by any ordinary process of 

 straining. 



Unclean condition of stable. A dirty condition 

 of the floors, walls and ceilings of a stable tends to 

 contaminate milk. Any condition in the stable that 

 affords a supply of floating dust at the time of milking 

 furnishes additional bacteria for milk 



Unclean condition of milker. The hands and 

 clothing of a milker may easily be loaded with bacteria 

 and thus become a source of infection. Particularly 

 objectionable is the filthy practice of moistening the 

 hands with milk when milking. 



Unclean utensils, especially the milk-pails, strain- 

 ers and milk-cans. The cracks and joints of all 



