36t> 



PHYSIOLOGICAL CHEMISTRY. 



Skimmed Condensed 

 milk. milk. 



89.6 



4.2 

 1.0 

 4.4 

 0.8 



14 



10 



49 ! 



2 



93.8 

 0.8 

 0.3 

 4.5 

 0.6 



The inorganic salts consist chiefly of calcium or sodium 

 phosphate and sodium and potassium chloride, but contain also 

 some magnesium and iron. 



The proteids consist mainly of casein with some albumin,, 

 the proportion being about as 9 to 1. 



Beside the constituents mentioned in the above analyses, 

 milk also contains a very small quantity of extractives, among 

 which are found peptone, kreatin, leucin, etc. The principles 

 which give to milk its peculiar odor have not yet been con- 

 clusively pointed out. 



Changes in milk. Soon after milk leaves the animal system 

 changes take place which are either of a physical or chemical 

 nature. The first change in milk, when allowed to stand for a 

 few hours, is a separation of the suspended fat globules towards 

 the upper part of the liquid, which gradually becomes loaded 

 with fat, forming a distinct layer over the liquid. This upper 

 layer having a slightly yellowish color (cream-color) is cream, 

 the watery liquid below having a bluish-white color is skimmed 

 milk. 



Another change taking place in milk (rarely after a few hours, 

 but generally after a day or a few days) is the coagulation of 

 casein, which takes place both in the cream and in the skimmed 

 milk, converting the whole into a thick, semi-liquid mass,. 



Including cane-sugar added by the manufacturer. 



