408 MANUAL OF MILK PRODUCTS 



With these few facts in mind, it is well to note the most im- 

 portant factors which influence the process of churning. These 

 factors are : 



(1) The percentage of butter-fat in cream. 



(2) The temperature of the cream. 



(3) Fullness of the churn. 



(4) Speed of the churn. 



(5) Breed of cows. 



(6) Individuality of cows. 



(7) Time in the period of lactation. 



(8) The feed of cows. 



(9) Acidity of cream. 



A brief discussion of these factors will bring out more clearly 

 the effect of each. 



(1) As noted above, the percentage of butter-fat determines 

 the proximity of the fat globules to each other and affects the 

 chances of their coming into contact during the churning or 

 agitation of the cream. 



(2) The temperature of these fat globules determines their 

 softness and the ease with which they adhere and form the 

 small granules. These unite with others until they become 

 visible in granules as large as wheat and corn kernels. 



(3) The fullness of the churn affects the amount of agitation 

 which is possible during the revolution of the churn. If the 

 amount of cream is small, it may adhere to the walls of the churn 

 and receive little or no agitation. On the other hand, if the 

 amount is too large, the churn will be so full that very little 

 room will be left for the agitation and concussion. 



(4) The speed of the churn also affects the amount of agita- 

 tion the cream receives. If it is revolved too rapidly, the cen- 

 trifugal force is sufficient to cause the cream to remain in one 

 end without causing agitation. If it is revolved too slowly, the 

 cream flows from one end of the churn to the other and does 

 not receive agitation or concussion. 



