PRODUCTION, COMPOSITION AND CHARACTERISTICS 15 



When whey is boiled down to a thick syrup and 

 left to stand, the sugar will crystallize out and may 



Cream 



Whole milk 



Skim milk 







Fat globules as they appear under the microscope 



be separated from the liquid, still holding in solution 

 the mineral matters. 



Mineral Matters. — These may be gathered as ash 

 by boiling off the water from this liquid or from the 

 whole milk and burning the rest, as all the constituents 

 except the ash belong to what in 

 chemistry is called organic matter, 

 which disappears in the air by burn- 

 ing. 



HOW TO TEST MILK 



Milk may be adulterated or de- 

 creased in value either by skimming 

 or by watering. In either case the 

 percentage of the most valuable con- 

 stituent, the butter-fat, is dimin- 

 ished. It is upon this fact that the most practical 

 test, the Babcock, is based. 



Dr. S. M. Babcock of 

 Madison, Wis. 



