CHURNING 277 



globules and by the viscosity of the cream. The larger the fat 

 globules the more rapid the formation of the butter granules 1 . 

 The effect of the concussion and the ease of coalescence are 

 intensified in the case of the large globules, because they strike 

 each other and the sides of the churn oftener and with greater 

 force than do the small globules. 



The viscosity of the cream diminishes the force of the con- 

 cussion. It obstructs the frequency of the collisions between 

 globules and detracts from the force of the impact when they 

 do collide, lessening their power of adhesion. 



Conditions which Affect the Churnability of Cream and the 

 Mechanical Firmness of Butter. The ease with which cream 

 churns is dependent on many and varying factors, some of these 

 factors have to do with the initial character of the cream as it 

 arrives at the factory, while others refer to conditions of the proc- 

 ess of manufacture. To the former group may be classed the size 

 of the fat globules, the chemical composition of the butterfat 

 and the viscosity of the cream. The second group includes such 

 factors as temperature of cream, degree of ripeness, richness of 

 cream, nature of agitation, fullness of churn, speed of churn. 



The following schematic classification may serve to illustrate 

 the numerous factors which enter into the churnability of cream, 

 and to clarify their logical relation to each other : 



1 Hunziker, Mills and Spitzer, Purdue Bulletin No. 159, 1912, p. 325. 



