No. 4.] MILK AND CREAM. 351 



combined with iron and magnesia. Very minute quantities 

 of urea, lecithin, kreatin, hypoxanthin, leucin and tyrosin 

 have also been recognized, formed without doubt from the 

 partial decomposition of the albumin during the process of 

 digestion in the animal body. 



Gases in small quantities, such as nitrogen, oxygen and 

 carbonic acid, also exist dissolved in the milk. 



While it is not possible to give any absolute figures for the 

 composition of milk, the following will show the approximate 

 relative proportions of the several ingredients : — 



Per Cent. 



Water, 87.00 



Fat, 4.00 



( Casein, 2.90 



... . ., j Albumin. 50 



Albuminoids, < T . , .. . 



1 Lactosjlobulin, ? 1C 



. > . . . . .15 



^ Lactoprotein, > 



Milk sugar, 4.75 



Ash 70 



100.00 



The following figures give the approximate compositions 

 of the milk of different breeds : — 



While the above figures can be taken as types, they do 

 not mean that every cow of a distinct breed will give milk of 

 the above composition. In fact, a great many Jerseys pro- 



• Containing milk sugar, curd and ash. 



