186 DAIRY FARMING 



method it is possible to recover about 90 per cent of the 

 cream. By the shallow-pan method from 75 to 80 per 

 cent is recovered. 



The centrifugal cream separator is now practical where 

 five or more cows are kept although it is often used for even 

 a smaller number. The separator makes it possible to re- 

 cover about 98 per cent of the butter-fat and to obtain the 

 cream in a condition that makes it possible 

 to produce the highest grade of butter. It 

 also results in a considerable saving of labor, 

 and the skim-milk is in the best possible con- 

 dition for feeding to calves. 



175. Ripening of Cream. This subject 

 requires considerable attention since the mar- 

 ket value of the butter is largely controlled 

 by the cream ripening. Cream should not 

 used for raising be held too long. When churned, it should 

 cream by deep- nave a pure, sharp, sour taste with no ob- 



setting system. 



jectionable taste, such as bitter, rancid, or 

 stale. Cream ripening is due to the development of bacteria. 

 Butter factories use a starter to help control the souring, 

 but this is not generally practical for the small farm, unless 

 considerable cream is handled. The proper ripening of the 

 cream is controlled by two things : first, by observing proper 

 cleanliness in every detail of milking, separating, and hand- 

 ling the cream ; second, by proper control of the temperature 

 of the cream during the ripening process. 



The following statement is based upon the assumption that 

 churning will be done two or three times weekly and not 

 daily. The best procedure under these conditions is to 

 keep the cream from the first milking at a temperature of 

 70 but not colder. This can be done by setting the can in 



