No. 4.] CLEAN MILK. 421 



CLEAN MILK: SUGGESTIONS FOE THE AVERAGE 



PRODUCER. 



HY 1". M. HAKWOOD, (iENEUAI. AUENT, STATE DAIRY BUREAU. 



Milk has been truly termed " the world's first food." The 

 importance of a pure, clean article can hardly be over- 

 estimated. The health, happiness, vigor and prosperity of 

 a peoi)le are in no small degree dependent upon the food 

 consumed, and especially is this true of the food of children, 

 who are later to become the men and women of the nation. 



As secreted from the udder of the healthy animal, milk is 

 in perfect condition. In the case of cow's milk, the calf 

 I'oaming in clean pasture with its mother has a monopoly on 

 the perfect article. The trouldes which come to milk most 

 frequently come from without, and are attendant upon arti- 

 ficial conditions. These conditions begin with the housing 

 of the animals, and do not end until the product is finally 

 consumed as food. Added to this is the present artificial 

 method of rearing babies on cow's milk. 



The changes which take place in milk are usually caused 

 by the presence and development of certain micro-organisms, 

 vegetable in their nature, known as bacteria; for example, 

 the lactic bacteria which cause souring. Milk also serves 

 as a medium for the conveyance of other forms, known as 

 pathogenic bacteria, all of which do not multiply in the 

 milk, but produce diseases, such as tuberculosis, typhoid 

 fever, scarlet fever, etc. 



The bacteria which cause changes in the milk itself multiply 

 with great rapidit}' after the milk is a few hours old, at cer- 

 tain temperatures. For instance, the bacteria Avhich cause 

 ordinary souring multi})ly most rapidly at about 70° F. to 

 80° F., and still others, though more slowly, at about 50° F. 



