DAIRY PRODUCTS. 77 



machine is rapidly rotated for five or six minutes. 

 Enough warm water is then added to each bottle to bring 

 the fat up into the neck. The bottles are whirled again 

 for two or three minutes, after which they are removed. 

 The amount of fat can be read in per cent on the neck 

 of the bottles. 



193. A dairy farmer has in his herd two cows, each 

 producing during the year 6,000 pounds of milk. By 

 using this Babcock tester he finds that the test of one is 

 3.2 per cent ; and of the other 5.8 per cent. What is the 

 difference in fat produced during the year by the two 

 cows ? 



194. At 25 cents per pound, what is the money value 

 of the butter fat yielded by the first cow. By the second ? 



195. This same farmer finds that last year one of his 

 cows gave 8,000 pounds of milk, the test of which was 

 3.2 per cent ; another cow gave 5,000 pounds, which tested 

 5.6 per cent. Which is the more valuable cow ? What is 

 the butter fat difference ? 



Important truth. The value of a cow depends upon 

 her ability to produce a large quantity of milk that shows 

 a high fat test. Neither the quantity nor kind of feed 

 influences the fat per cent. It may influence the quantity 

 produced, but not the quality. The latter is a fixed char- 

 acter with the cow just as color or breed is fixed. The 

 Babcock tester enables the owner to know the quality of 

 the milk for every cow. 



Relation of fat to butter. The churn collects fat 

 globules into butter. When thus manufactured the com- 

 mercial product contains fat, water, salt, milk, sugar, 

 and some casein. Hence the fat when churned produces 

 on an average one-sixth more butter than the fat content 

 of milk or cream. 



