CHURNING 295 



cussion of the fat globules is lessened, and the churning process 

 is retarded. For maximum concussion, therefore, the churn 

 should revolve at the highest speed consistent with the absence 

 of centrifugal motion of the cream and that permits the cream 

 to fall from side to side of the churn. The exact speed which 

 accomplishes this condition varies somewhat with make of 

 churn, the fullness of the churn and the richness of the cream. 

 Under average normal conditions it has been found that the 

 churn should revolve at a maximum speed of about thirty 

 revolutions per minute. 



Amount of Cream in the Churn. Other conditions being 

 the same, when the churn is about one-third to one-half full 

 the cream is subjected to the maximum concussion. The am- 

 ount of cream in the churn bears a direct relation to the agita- 

 tion of the cream. The fuller the churn the more difficult it 

 is to produce thorough agitation and the more time is required 

 for the formation of the butter granules. When the churn is 

 too full the cream is also more prone to foam and swell, which 

 makes the completion of the churning next to impossible, with- 

 out first removing some of the cream. Under such conditions 

 there usually is also excessive loss of fat in the buttermilk. 



With too little cream in the churn, the cream, if it is rich 

 in butterfat and thick, is prone to adhere toi the sides of the' 

 churn, it will then either revolve with the churn or slide back 

 along the side of the churn. In either case the process of 

 churning is delayed. If the cream is thin, the granules are dif- 

 ficult to gather. Too little cream in the churn has the additional 

 disadvantage that the control of the temperature is difficult, and 

 in case of a warm churn room, the cream may warm up con- 

 siderably and the butter is apt to be excessively soft. In the 

 case of thin or^ medium rich cream and at a low temperature 

 the butter granules of small churnings in a large churn are 

 subjected to excessive agitation, striking against the sides of the 

 churn with much force. This makes them very compact, inten- 

 sifying the expulsion of water, thus tending to reduce the 

 overrun. 



From the above discussion it should be clear that, for 

 quickest and best results, the size of the churning should be 



