CONDITIONS AFFECTING THE CHURNABILITY OF CREAM 249 



butter when the cream is in such a condition, but by following 

 the plan outlined enough of the specks can be removed from the 

 butter so that its commercial quality will not be injured. -The 

 degree of ripeness of cream does not have any effect upon the 

 composition of the butter, except in increasing the curd content as 

 mentioned. 



Nature of Agitation. The nature and degree of agitation of 

 cream affect the churnability considerably. Many different 

 kinds of churns are on the market at the present time. The 

 rotary drum-churns, now used almost universally in this country, 

 are claimed to give the greatest degree of agitation; that is, 

 providing the churn revolves at a proper rate of speed. If 

 the speed is so great as to cause the cream to be influenced by 

 the centrifugal force generated, rotating it with the churn, then 

 no agitation will take place. Consequently the churning 

 process will be delayed, if not entirely prevented. If the 

 speed of the churn is too slow, the degree of agitation of the 

 cream will not be at its maximum, as the cream will tend to 

 remain at the lowest portion of the churn without being agitated. 



In the old-fashioned dash-churn the cream was not exposed 

 to much agitation. In Europe the upright barrel-churn with 

 rotary stirrers inside is mostly used. It is slower than American 

 churns, but gives good satisfaction. 



Extensive investigational work conducted by the American 

 Association of Creamery Butter Manufacturers, under the 

 direction of one of the authors, has shown that there are 

 several factors which have a direct bearing upon the exhaustive- 

 ness of the churning of cream. With very sour cream that 

 has been pasteurized, the loss of fat in buttermilk is much 

 larger than is generally recognized by buttermakers. The 

 average loss of fat in buttermilk, according to hundreds of 

 analyses made by the American Association of Creamery 

 Butter Manufacturers, is more than five-tenths of one per cent. 



The loss of fat in buttermilk varies somewhat with the 

 seasons of the year. During the hot weather in the summer 

 months, especially in the flush, the loss of fat in buttermilk 

 is greater than in the fall and winter months. One creamery 



