54 



THE STORY OF MILK 



It has been attempted to make the brine freezers 

 continuous, the cream mixture being fed into the ma- 

 chine at one end and discharged frozen at the other. 

 But this system has not so far been successful, and in- 



Power brine freezer 



termittent cr batch freezers are most practical yet 

 both for hand and for power. 



Rich material, frozen in a good machine, whether 

 intermittent or continuous, will expand from 50% to 

 100%, and the original material should not fill the 

 freezer-can more than half full. 



The manufacture of ice cream has been the subject 

 of study and experiments for years in the Dairy De- 

 partment of the Agricultural College at Ames, Iowa, 

 where Professor M. Mortensen has worked out a com- 

 prehensive classification from which any manufacturer 



