272 CHURNING 



The skim milk (now called buttermilk), in excess of that por- 

 tion that is incorporated in, or adheres to, the surface of the 

 butter granules, recedes and "wheys off," the butter granules 

 separate out, and the butter "breaks." This point is reached 

 after the majority of the butter granules have outgrown their 

 original microscopic size and have become large enough to be 

 readily visible to the naked eye. 



Pig. 43. Water droplets in butter, magnification 740 



With the "breaking" of the butter, the emulsion changes 

 from a fat-in-skim milk emulsion as represented by the cream, 

 to a buttermilk-in-fat emulsion, as is represented by the butter. 

 The fat globules cease to exist as units. Butter is a mass of 

 butterfat into which have been emulsified small divided units, 

 or droplets, of buttermilk. Butter represents an emulsion in 

 which the fat is the continuous phase and the hydrated colloid 

 or buttermilk the divided or dispersed phase. 



While, under normal conditions of churning, the churning 

 process occupies from about 40 to 60 minutes, the actual "break- 

 ing"of butter happens with almost instantaneous suddenness. 



