152 NEUTRALIZATION OF SOUR CREAM 



The extent and value of this expulsion of gases and the con- 

 sequent improvement of the flavor of the butter, made from 

 cream neutralized with carbonates, are however much over- 

 estimated. The expulsion of carbondioxide and other gases 

 that miay be present in the cream will occur to a large extent 

 in all cream, whether neutralized or not, during the process 

 of pasteurization. In fact, the flavor-improving effect of car- 

 bonate neutralizers is largely imaginary. If these claims were 

 well-founded, it should be possible to make No. 1 butter from 

 Grade 2 cream. This cannot be done. Distinct off-flavors in the 

 cream do not disappear by the use of these neutralizers. 



On the other hand, the use of carbonate and bicarbonate 

 neutralizers has the serious disadvantage of robbing the 

 operator of the ability to check the accuracy of his work, be- 

 cause the carbondioxide formed in the cream when these neu- 

 tralizers are used, reacts acid, causing the test to show a higher 

 acidity than the lactic acid content of the cream represents. These 

 tests could be made to show the correct acidity by boiling the 

 sample of cream to be tested, or by blowing air through it, 

 both of which practices would expel the carbondioxide, but 

 these practices are objectionable in practical creamery opera- 

 tion, because of the d.elay their application would inevitably 

 cause in the work and also because of the danger of incom- 

 plete execution. Methyl orange indicator, which is not affected 

 by the carbondioxide, might be used instead of phenolphthalein, 

 but it is not suitable, because it fails to show a definite, sharp 

 end reaction in weak organic acid such as lactic acid. 



Because of their generation of carbonic acid gas in sour 

 cream, the use of carbonates and bicarbonates often presents 

 mechanical difficulties, causing the cream to foam up and over 

 the vat, unless such neutralizers are used with care. This 

 is especially true in the case of high-acid cream and when the 

 temperature of the cream is relatively high at the time the 

 carbonate is added. 



Sodium carbonate and sodium bicarbonate are more 

 troublesome in this respect than calcium carbonate, the for- 

 mer being readily soluble and acting quickly, while the cal- 

 cium carbonate is practically insoluble in water and therefore 



