250 CREAM 



The experienced operator can usually detect the proper 

 degree of ripeness by the taste and appearance of the cream. 

 In order to assist him in detecting the proper degree of ripe- 

 ness he should use a convenient and accurate test to determine 

 the per cent of acid, such as the Farrington Alkaline tablet 

 test, the Mann's acid test or the Marshall acid test. These tests 

 are based on the principle that normal solutions of alkalies neu- 

 tralize equal portions of normal solutions of acids. The alkali 

 usually used is sodium hydroxide with phenolphthalein as an 

 indicator, which turns pink in an alkaline solution and remains 

 colorless in an acid solution. For detailed directions of testing 

 cream for acid see Chapter XXII on Chemical Tests and Analy- 

 ses. 



Starter Ripening Instead of Cream Ripening. As previ- 

 ously stated, the species of lactic acid bacteria, which have been 

 found the most suitable ferments and which can be used to 

 advantage in cream ripening, attack exclusively the non-fatty 

 constituents of cream and particularly the lactose, breaking it 

 down into lactic acid. The most prominent of these species 

 are Streptococcus lacticus and Bacterium lactis acidi. Since 

 the non-fatty serum of the cream is very largely all washed 

 out of the butter it would seem that the flavor and aroma 

 developed in the serum and exclusively outside of the fat glob- 

 ules would also be washed out of the butter. This, however, 

 is not the case. The highly aromatic Isigny 1 butter for instance 

 is washed exceptionally thoroughly. The reason for this lies 

 in the fact that butterfat possesses thej property of absorbing 

 flavors and aromas from volatile oils and other substances. This 

 property has long been recognized and is extensively made use 

 of in the manufacture of perfumes. This shows that the flavor 

 and aroma developed in the serum are taken up by the fat 

 globules. 



From the above facts it may reasonably be assumed that 

 the desired butter flavor and aroma can be acquired by their 

 addition to the cream or butter, in the form of a properly ripened 

 starter, in the place of the process of cream ripening. Instead 

 of developing these flavors in the cream by means of the cream 



1 Isigny butter is made on the dairy farms, in the vicinity of Isigny, Nor- 

 mandy, France. This butter has established an enviable reputation for fine 

 flavor, and keeping quality, on the continent of Europe. 



