CREAM RIPENING. 77 



during the ripening period which is one of the most 

 critical periods in the handling of cream. Quick 

 ripening of cream is as a rule associated with the 

 use of a large per cent of starter of high quality to- 

 gether with proper temperatures. On the other hand 

 slow ripening of cream whether intentional or other- 

 wise is associated with the employment of low tem- 

 peratures and the use of a small amount of starter 

 or a starter of poor quality. The result usually is 

 that cream ripened in this way will develop sour, 

 flat, slightly bitter and other undesirable flavors. 



102. How to preserve the quality of lactic acid 

 in cream. When cream is ripe — that is when enough 

 acidity has developed, it should be cooled at once to 

 a temperature low enough to prevent the develop- 

 ment of acidity to any appreciable extent before 

 churning. By cooling cream when ripe to 50° P. 

 or lower the lactic acid can be preserved in good 

 condition for about fourteen hours. Cool cream low 

 enough to render the various fermentations inactive 

 and the quality of the lactic acid will be preserved. 



103. Acidity in relation to the per cent of fat in 

 cream. Since the development of lactic acid takes 

 place only in the serum of cream and the per cent 

 of serum varies in relation to the variations in the 

 fat content, it seems but reasonable that the acidity 

 in cream ought to vary in relation to the per cent of 

 fat in cream. The lower the per cent of butter fat 

 in creajn the more serum it contains and the higher 

 the per cent of butter fat in cream the less serum it 

 contains. The per cent of serum in cream varies 

 inversely as the per' cent of fat varies, and the lactic 



