6 DAIRYING 



who may handle the milk up to the time it is delivered to the 

 factory or to the city consumer. 



Since the number of germs in milk is due largely to the 

 way in which it is handled, some cities have passed ordinances 

 requiring milk sold in that city to contain not more than 500,000 

 bacteria per cubic centimeter. Other cities have adopted a 

 different standard, but this is about the average figure. 



There is a strong tendency on the part of health officers and 

 of manufacturers of a high quality of dairy products to insist on 

 clean milk and a frequent inspection of the cow stables, as well 

 as the methods of handling the milk at the farms, is being en- 

 forced to a greater extent each year. 



THE KIND OF GERMS IN MILK. 



674. It is claimed at the present time that there have been 

 found at least 200 different kinds of bacteria in milk. These may 

 in a general way be divided into the good, the bad, and the 

 indifferent gerrns. The lactic acid bacteria which cause milk to 

 sour, may be classed under the head of "good" germs, in so far 

 as they aid in the development of desirable flavors in butter and 

 in cheese after it is made, but these same bacteria may spoil the 

 milk for cheese-making if they are too numerous in the fresh 

 milk. 



675. Under the head of "bad" germs may be included the 

 disease producing bacteria and those that cause bad flavors in 

 milk, butter and cheese. The "indifferent" germs include a, 

 large number that grow rapidly in milk, but have no particularly 

 injurious or beneficial effect on dairy products, or on the con- 

 sumer of such products. It is true, however, that the entire 

 absence of germs helps the flavor of milk and cream while their 

 presence may spoil these products, and when one realizes that 

 16 million bacteria may grow from one bacterium in 24 hours, the 

 necessity of protecting milk from dirt, dust and dirty utensils 

 can be readily understood. Each hair that drops in the milk 



