SECTION LXII. MAKING BUTTER 



THE fat in milk is in the form of very small, round par- 

 ticles, called globules. Since fat is lighter than milk, the 

 fat globules rise to the surface, forming the cream. They 

 rise more completely if the milk is cooled promptly after 

 milking. Hence, milk is generally promptly poured into 

 shallow pans, or quickly cooled in deep cans placed in 

 cold water. But any method of removing the fat globules 

 that depends upon their rising to the surface leaves many 

 of them entangled in the skimmed milk. 

 When shallow pans are used, about one 

 fourth of the fat may be lost in the skimmed 

 milk. However, the cream separator (Fig. 

 2 1 1 ) removes nearly all of the fat. It does 

 this by the rapid revolution of the metal 

 bowl through which the milk is passing. 

 The bowl revolves six thousand times or 

 more per minute. The rapid motion throws 



FIG. an. A HAND the heavier part of milk to the outer 

 CREAM SEPARATOR edge of the bowl> from which it runs Qut 



as skimmed milk. The cream, being lighter, collects 

 nearer the center of the bowl, and overflows. 



Ripening cream for churning. While many kinds of 

 germs are harmful to milk, there is one kind of germ 

 which the dairyman needs in milk or cream intended for 



3* 



