ICE-CREAM MACHINERY 



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Ice Crusher. This is a great labor-saving device and 

 is indispensable where large quantities of ice are crushed. 

 The machine breaks the ice into pieces of a more uniformly 

 small size than can possibly be done by hand with an ax or 

 stomper. 



Homogenizer. This is one of the latest inventions in 

 ice-cream machinery. As its name indicates, it is a ma- 



FIG. 40. A six-cylinder Progress homogenizer. 



chine for converting liquids such as cream into a homo- 

 geneous mass. This is accomplished by breaking the fat 

 globules into such fine particles that they are unable to 

 rise to the surface, but remain incorporated in the liquid. 

 The machine consists of a pump or a series of pumps which 

 discharge the liquid against the homogenizing valve. 

 This latter may be compared to a safety valve which blows 

 off at a pressure of from 2000 to 3000 pounds per square 

 inch. The valve disk is made of agate and closes per- 



