228 Testing Milk and Its Products. 



muffle oven at a low red heat. Direct heat should not 

 be applied in determining the ash in milk, since alkali 

 chlorids are likely to be lost at the temperature to which 

 milk solids have to be heated to ignite all organic carbon. 



Example: Weight of porcelain dish+milk... . 49.0907 grams. 

 Weight of porcelain dish 28.3538 grams. 



Weight of milk 20.7369 grains. 



Weight of dish+milk, after ignition 28.5037 grams. 

 Weight of dish 28.3538 grams. 



Weight of milk ash 1499 gram 



Per cent, of ash=4^f^^=.72 per cent. 



The residue from the determination of solids by tht 

 Alternate Method given (252) may also be used for the 

 ash determination. 



B.— Cream, Skim milk, Butteb milk. Whey, Con- 

 densed MILK. 



262. The analysis of these products is conducted in 

 the same manner as in case of whole milk, and the same 

 constituents are determined, when a complete analysis 

 is wanted. Skim milk, butter milk, and whey con- 

 tain relatively small quantities of solids, and espe- 

 cially of fat, and it is, therefore, well to weigh out a 

 larger quantity than in case of whole milk ; if possible, 

 toward 10 grams. The acidity of sour milk and butter 

 milk must be neutralized with sodium carbonate pre- 

 vious to the drying and extraction, as lactic acid is solu- 

 ble in ether and would thus tend to increase the ether- 

 extract (fat), if not combined with an alkali previous 

 to the extraction. 



