CREAM RIPENING 249 



erally producing odors and flavors detrimental to the quality of 

 good butter and shortening its life. The high acid in overripened 

 cream in itself accelerates the development of certain other 

 classes of micro-organisms, such as the molds which demand 

 an acid medium for maximum growth, and whose presence in 

 butter is exceedingly objectionable. From the bacteriological 

 point of view, therefore, the overripening of cream is highly 

 undesirable, it deteriorates the flavor and keeping quality of 

 the butter. 



Overripening does prove harmful to butter also from the 

 chemical standpoint. The proteids of cream and butter are prone 

 to undergo chemical changes which invite further decomposition, 

 giving the butter off-flavors tending towards metallic and fishy 

 flavor defects and hastening its deterioration in storage. 



For these reasons great care should be exercised in stopping 

 the ripening process before it has developed too far, by promptly 

 cooling the cream to 50 degrees F. or below. When facilities 

 for prompt cooling are lacking, the cooling of the cream should 

 be started before the desired degree of acidity is reached, mak- 

 ing due allowance for additional acid development during the 

 cooling process and until the cream has reached a low enough 

 temperature to completely check further fermentation. 



Where cream is churned only once or twice per week, as 

 is often the case in small creameries and during the months of 

 small supply, it is advisable to keep all cream at a low tempera- 

 ture until twenty-four hours before churning time and then raise 

 the temperature for the ripening process sufficiently to com- 

 plete the ripening, if the cream "must" be ripened, until about 

 three hours before churning when it should be cooled to the 

 churning temperature and held there. 



Methods to Determine the Desired Degree of Acidity. 



When the cream has reached the proper degree of acidity it 

 usually has a clean, mild acid flavor, pleasant to the palate. 

 The viscosity of sweet cream has disappeared and the cream 

 has a granular body and glistening luster. The creamy yel- 

 lowish color has changed to a whitish tinge. These changes 

 in body and color are due to the precipitation of the casein into 

 a granular form. 



