142 MODERN METHODS OF TESTING MILK 



are several large pieces of ice. Stir the liquid contin- 

 uously, alternating- a circular and crosswise motion, 

 until the fat hardens, when it can be easily collected 

 into one lump by means of the wooden stirrer, if it is 

 oleomargarin ; but, if butter, the fat will form little 

 granules and can not be collected in one lump. When 

 milk is used in the test, it should contain as little fat 

 as possible. In this test ''renovated" butter behaves 

 like genuine butter. 



ADULTERATIONS OF CHEESE 



Only two kinds of adulteration are common in 

 American cheddar cheese: (i) The removal of fat in 

 varying degrees producing so-called skim-cheese, and 

 (2) the use of fat other than milk-fat, producing the 

 so-called filled cheese. Harmless coloring matter is 

 allowed. Cheese containing less than ^2 per cent, of 

 fat can be regarded as having been made from milk 

 containing less than its normal amount of fat. The 

 per cent, of fat in filled cheese is generally lower than 

 in cheese made from normal milk. 



