176 



THE ANALYSIS OF MILK. 



Carbohydrates. Milk sugar, the carbohydrate of milk, con- 

 stitutes between 4.5% and 5% of the milk. 



Mineral matter. The ash, as stated by Leach (2), does not 

 represent the true mineral content of milk, since in the process 

 of incineration some of the constituents are altered. For 

 instance, citric acid occurring hi small quantities in normal 

 milk will appear in the ash as carbonic acid in combination. 

 Several other illustrations could be given. 



The ash, in all probability, is the least variable of any of the 

 ingredients of milk and for that reason is often made the basis 

 of calculating the composition of an original milk from the 

 analytical results of the examination of a condensed milk. 



Solids of milk. The protein, fat, sugar and ash comprise 

 what are designated as milk solids. The sugar, protein and 

 mineral matter constitute the solids not fat. These latter, with 

 the water, are known as the milk serum. 



The average composition of milk, its derivatives and colos- 

 trum, are shown in the following table. 



TABLE VIII. 

 COMPOSITION OF MILK, ETC. 



Effect of feeding on the composition of milk. The idea is 

 prevalent among dairymen throughout the country that the 

 quality of the milk may be improved by modification of the 

 feeding of the cows. The problem has been investigated many 

 times by eminent authorities. Conclusions have been reached 

 as follows : 



1 . If a cow is being properly fed, that is, receiving a balanced 

 ration suitable for her individual needs, the quality of the milk 



