92 



table previously given on stimmed milk and its percentage of 

 fat. The inspector's report is to be verified by an exact determi- 

 nation of fat and solids. 



Mixing of tvhole and shimmed tnilk may be inferred by the 

 data given above. 



Foreign substances in milk : The substances most generally 

 applied have been given on pages 41-43. Also the methods used 

 for their detection. 



Properties of Normal Cows' Milk and 

 Market Milk. 



Normal cows' milk and milk of commerce must possess an 

 agreeable normal odor and taste — i. e., it should not emit a dis- 

 agreeable odor or possess an alkaline or sour taste. The whole and 

 normal milk of commerce, obtained by mixing the milk of a num- 

 ber of cows, has an average composition as follows : 



"Water and volatile substances 87.5 per cent. 



Salts 0.5 " 



Fat 3.5 " 



Albuminates 4.0 " 



Milk sugar 4.5 " 



Its average specific gravity, according to many thousands of ex- 

 periments, ranges from 1.029 (29°) to 1.033 (33°). It contains in 

 the minimum 3 per cent, of fat and 12.5 per cent, total solids. 



For good and normal cows' milk, these points constitute an in- 

 disputable truth. Each milk which does not come up to this 

 standard is a poor article. • 



11 per cent, of solids, 2 to 1^ per cent, of fat, and a specific 

 gravity of from 1.031 to 1.035, indicates that siich milk has suffered 

 the loss of one-half its cream. 



9^ to 9 per cent, solids, 1 to ^ per cent, fat, and a specific 

 gravity of from 1.0325 to 1.036, indicates thai the milk is skimmed 

 entirely of its cream. 



The Aim of Governmental Control of the 

 Quality of the Milk Supply. 



The inspection of the milk brought upon the market aims not 

 only at the detection of the adulterations, but must be instituted 

 to guarantee to the public that the article which they receive is of 



