DAIRY PRODUCTS 



373 



albumen, and .75 pounds of ash. The butter fat is the most 

 important and valuable constituent of milk. 



486. Butter fat. Butter fat occurs in milk in small globules 

 (Fig. 1 86) which vary greatly in size. Forty thousand of the 

 smallest globules placed side by side would measure an inch, 

 while twenty-five hun- 

 dred of the largest 



when placed together 

 would fill a like space. 

 When these globules 

 are matted together by 

 being churned, butter 

 is formed. Rich milk, 

 such as that given by 

 the Jersey cow, contains 

 larger fat globules than 

 does a lower-testing 

 milk, such as is pro- 

 duced by the Holstein 

 cow. Milk containing 

 large globules will sepa- 

 rate more completely 

 and in less time, and 

 will also churn more 

 readily than milk con- 

 taining small globules. 



One hundred pounds Professor S. M. Babcock of the University of Wis- 

 consin, by means of the milk tester, has enabled 



01 the Ordinary COm- m any dairymen to discover and dispose of the " star 

 mercial butter Contains boarder" cow. He has taught dairymen that "it is 



performance which counts " 



about I pound of curd, 



2 pounds of ash, 13 pounds of water, and 84 pounds of fat. 



487. Other components. The casein and albumen make up 

 the protein of milk which is used by the young animals to make 

 blood, muscle, bone, skin, hair, hoof, and horn. The casein of 

 milk forms a large part of cheese. The protein remains in the 

 skim milk, which explains why skim milk is so valuable as a feed. 



FIG. 185. The inventor of the Babcock milk 

 tester 



