42 DAIRYING 



The presence of air is not necessary for cream ripening as the 

 lactic acid bacteria grow in the presence and in the absence of air. 

 Aeration and stirring are beneficial during cream ripening, as they 

 prevent a musty smell in the butter and distribute the ferments 

 uniformly through the mass of the cream. 



RELATION BETWEEN HARDNESS OF THE FAT AND 

 THE BUTTER FLAVOR 



471. Butter fat is a very complex compound, but for the pur- 

 pose of butter-making it may be considered as made up of the hard 

 and the soft fats. The relative proportion of these components 

 affects the body and texture of the butter. The proportion is in- 

 fluenced by the cow's feed and by her period of lactation. When 

 cows are fresh and when they receive a liberal supply of green feed 

 the relative proportion of the soft fats is greater and the butter is 

 often much softer and melts at a lower temperature than is the 

 case in' the latter part of the lactation period or when cows receive 

 dry feed exclusively. 



The hardness of butter may be an indication of its flavor. 

 High flavored butter is usually softer than low flavored butter and 

 hard, tallowy butter is inclined to be tasteless. 



The relation between the amount of hard and of soft fats in 

 butter is not changed, however, by the cream ripening process. It 

 is either a breed or an individual characteristic of the cow or it is 

 subject to the changes already mentioned in the period of lactation 

 and the feed that the cows receive. 



It will thus be seen that the fermentations which take place 

 during the ripening of the cream are not the only source of butter 

 flavor. These ferments are however of great importance, and 

 their propagation and control is discussed under the head of Start- 

 ers in lesson VI. 



2. The Effect of Ripening on Churning. It has already been 

 stated that one of the reasons for ripening cream is to aid in churn- 

 ing the cream in a reasonable length of time. A well ripened 

 cream will churn under ordinary circumstances in about 45 minutes, 



