40 Dairy Bacteriology. 



"sanitary" or "certified" as the method of handling the 

 herd is often nnder the control of ontside parties (phy 

 sicians or health board) who certify to the regulations 

 that are followed. 



FIG. 9. Bacterial content of milk handled in ordinary way. Each spot rep- 

 resents a colony growing on gelatin plate. Compare with fig. 10, where same 

 quantity of milk is used in making culture. Over 15,000 bacteria per cc. in this 

 milk. 



The question may arise as to the necessity of these 

 precautionary measures if the milk is to be used for or- 

 dinary factory purposes. While certain bacteria are 

 essential in the butter and cheese industry to secure a 

 normal and characteristic fermentation, yet it is better to 

 have the germ life reduced to the lowest numbers than 

 to have the raw milk infected through slovenly methods 

 of handling. If this is done, the maker has the fer- 

 mentation under his control, and by the addition of a 

 starter which he can choose, he can vary the character of 

 the product to suit the demands of the trade, which he 

 cannot do, if the raw milk is brought to him in a dirty 

 condition, and in an advanced stage of fermentation. 



