38 FIRST LESSONS IN DAIRYING 



as a sandy mud may be thick and flow with diffi- 

 culty yet not cling together as a viscous syrup. 



In the less viscous ripe cream the fat globules 

 seem to move more freely, gathering together 

 with greater ease as a result of the agitation of 

 churning. 



Improved keeping quality. The bacteria which 

 produce lactic acid do not injure the keeping quality 

 of the butter. If during the ripening the putrefy- 

 ing and objectionable forms which do not thrive in 

 the presence of the lactic acid have been held in 

 check, the keeping quality of the butter will be 

 improved. 



The bacteria. Fortunately, nature has provided 

 that the bacteria which will produce the desired 

 flavor are most likely to predominate in the cream 

 if the milk has been handled under good, cleanly 

 conditions. The ripening of the cream under farm 

 conditions usually depends on the bacteria which 

 have accidentally gotten into it. This is called the 

 natural method as distinct from the use of a starter 

 which may be home-made, as butter milk or cream 

 saved from the last churning, skim milk which has 

 been ripened, or a commercial starter prepared with 

 a commercial culture of flavor-producing bacteria. 

 Ordinarily, good results can be obtained by keep- 

 ing the cream sweet at a temperature of 45 to 50 

 until enough is gathered for a churning, which 

 should not be more than two or three days. The 

 entire lot should be thoroughly stirred each time 

 new cream is added. Eighteen to 24 hours before 

 churning time the cream should be warmed to a 



