238 MANUAL OF MILK PRODUCTS 



the use of special jackets for the cans or by shipment under 

 ice or in refrigerator cars. 

 The ripening of cream. 



The ripening process covers the changes which take place in 

 cream up to the time that it is placed in the churn, and more 

 particularly its treatment after being received at the creamery. 

 Next to the quality of the fresh cream, the quality of the finished 

 butter is dependent on the ripening process more than on any 

 other factor. The purpose for which cream is ripened is to 

 give the butter the flavor and aroma characteristic of butter 

 of high quality. While the chief purpose of the ripening is to 

 give the proper flavor, it also increases the ease and efficiency 

 of churning. However, butter may be made without the cream 

 being ripened at all, this method being now used to quite an 

 extent in the manufacture of what is known as sweet cream 

 butter, which finds a ready sale in many of our markets. 



In the case of most creamery butter, the cream is subjected 

 to the ripening process before churning. This ripening process 

 is the result of the action of certain types of bacteria growing 

 in the cream. The chief change produced is the breaking down 

 of the milk-sugar and the formation of lactic acid by the action 

 of the lactic acid bacteria. While it is not definitely known 

 that all of the changes taking place during the ripening process 

 are the result of the lactic acid bacteria, the desirable changes 

 are very largely associated with this fermentation. The ripen- 

 ing process may be accurately controlled by the use of definite 

 temperatures and by the use of starters. Cream may be ripened 

 naturally by holding at temperatures which favor the desired 

 types of bacteria, but, in the best creamery practice, this method 

 does not control the ripening process with sufficient accuracy. 

 When a starter is used, it may be added to the raw cream or the 

 cream may be pasteurized in order to remove the undesirable 

 bacteria present in it. The preparation and use of starters for 

 butter-making is well discussed by Bouska as follows : 



