26 



MILK HYGIENE 



following composition: fat 3.33 per cent., casein 3.12 per cent., albu- 

 min 5.96 per cent., lactose about 4.9 per cent., and ash 0.59 per cent. 



The rabbit and the reindeer give milk particularly rich in fat and 

 especially concentrated, but poor in lactose. The milk of the 

 elephant shows very great fat and sugar content and comparatively 

 little protein. 



A milk differing greatly from the usual is that of the whale. 

 It contains only from 41.0 per cent, to 48.0 per cent, of water, and 

 fat in the enormous proportion of 43.0 per cent, to 45.0 per cent. 

 There is 7.5 per cent, to 11.0 per cent, of protein and only about 

 1.3 per cent, of sugar. 



The table below shows the average analysis of human 

 milk and of the other kinds of milk used as food for man : 



Water . . 

 Casein . . 

 Albumin 



Fat 



Lactose . 

 Salts 



Woman. 



87.92 

 0.58 

 0.52 

 3.43 

 7.12 

 0.25 



IV. VARIATIONS IN THE COMPOSITION 

 OF COW'S MILK 



It has already been stated that the composition of 

 the milk of the cow, as well as that of other animals, may 

 vary more or less. So far as the variations of cow's 

 milk are concerned, they are not very great, still they 

 are of suflScient importance to make it necessary to 

 take them into consideration in connection with its pro- 

 duction, sale and control. The above figures give ap- 

 proximately the average composition of cow's milk and, 

 of course, correspond with the composition of market 

 milk, which consists of a mixture of milk of several or 

 many cows.^ The separate constituents vary in quantity 



' These are Danish figures; in America the average for market 

 milk is higher. [L. P.] 



