78 MILK PRODUCTS. 



This multiplied by 6.38 gives casein. 



The fat may be estimated by the centrifugal method, 

 as follows : — 



About 5 grams of the mixed cheese are weighed 

 and transferred to the bottle, the last portions being 

 washed in with the aid of water. A few drops of am- 

 monium hydroxid are added, and sufificient water to 

 make the liquid about 15 c. c. The liquid is warmed 

 with occasional shaking, until the cheese is well disin- 

 tegrated, and then treated as a sample of milk. The 

 percentage of fat is found by multiplying the percent- 

 age reading by 15.45 ^"d dividing by the number of 

 grams of cheese taken for analysis. 



Chrome yellow has been found in the rind of cheese. 

 It may be detected by ashing the same in a porcelain 

 crucible, assisting the burning of the carbon by a 

 little nitric acid, and applying the usual tests for lead 

 and chromium. 



Cheese contains small amounts of milk sugar, lactic 

 and other organic acids. 



