CHAPTEE X 



Testing of Milk 



A SHOET description of the methods in use for 

 testing milk may be given. To do so, various 

 methods may be employed. These may be divided 

 into two classes : (1) tests and (2) chemical analysis, 

 the former of which depend chiefly on the physical 

 properties of milk. Taking the former class of tests 

 first, these are as follow : 



1. Determination of the percentage of fat l>y meas- 

 uring the thickness of the layer of cream thrown up 

 on allowing it to stand for some time. 



2. A determination of the fat l>y optical tests. 



3. Determination of the fat ~by the amount of "butter 

 the milk yields. 



4. Determination of the fat "by the addition of 

 certain reagents, etc. 



5. Testing the milk Ity determining its specific 

 gravity. 



1. Testing Fat by Amount of Cream. With 



