CHAPTER XIV. 



CHEMICAL ANALYSIS OF MILK AND ITS 

 PRODUCTS. 



246. An outline of the methods followed in determin- 

 ing quantitatively the main components of milk and its 

 products is given in the following for the guidance of 

 advanced dairy students. This work cannot be done 

 outside of a fairly well-equipped chemical laboratory, 

 or by persons who have not been accustomed to handlin;.' 

 delicate chemical apparatus and yiassware, analytical 

 balances, etc., and who have not a knowledge of, at 

 least, the elements of chemistry and chemical reactions. 



A.— Milk. 



247. In a complete milk analysis, the specific gravity 

 of the milk is determined, and the following milk com- 

 ponents : water, fat, casein and albumen, milk sugar, 

 and ash. The methods of analysis described in the fol- 

 lowing are those adopted by the Association of Official 

 Agricultural Chemists of North America, which, with 

 but slight modifications, are in general use in the chemi- 

 cal laboratories of all American experiment stations and 

 agricultural colleges.' 



248. a. Specific gravity is determined by means of 

 a picnometer or specific-gravity bottle, since more ac- 



' Tbe complete methods of analysis adopted by the Association of 

 Official Agricultural Chemists are published by the Bur. of Chemistry 

 of the D. S. Department of Agriculture ; see Bull. Xo. 107, pp. 117-128. 



