178 NEUTRALIZATION OF SOUR CREAM 



result of neutralization. Ramsay 1 found the following differ- 

 ences in curd content. 



Butter Made From Per cent Curd 



Unneutralized Cream 1.28 



Cream treated with Sodium Bicarbonates 87 



Cream treated with Calcium Carbonate 72 



The above analyses show a rather unusually high per cent 

 of curd in butter made from both, neutralized and unneutral- 

 ized cream. When butter is washed properly the curd content 

 generally averages several tenths per cent lower. However, they 

 are valuable because they show the relative reduction of curd 

 content due to neutralization. 



The decrease in the curd content may be explained by the 

 fact that the neutralizer causes the precipitated curd to be 

 firmer, more grainy and to separate more completely from the 

 serum. This is especially the case with lime-neutralized cream, 

 but even sodium-neutralized cream has a firmer curd than un- 

 neutralized cream. In this firmer condition more of the curd 

 passes into the buttermilk and less is taken up by the butter. 

 A J similar difference is noted between butter made from sour 

 and sweet cream. In sweet cream, the curd is present in a 

 more colloid condition which sticks to the butter particles and 

 causes such butter to have a higher curd content than sour 

 cream butter. 



The butter made from lime-neutralized cream contains 

 slightly more calcium than butter made from untreated cream. 

 Wichmann 1 found a slight increase in the calcium oxide of the 

 salt-free ash of neutralized cream butter, as well as in the butter 

 itself, and he claims that when the calcium oxide content of 

 butter exceeds .025 per cent, there is strong indication that such 

 butter was made from limed cream, provided that the salt added 

 to the butter did not contain calcium salts. The slight increase 

 in the calcium oxide of lime-neutralized butter is in all prob- 

 ability due to the calcium attached to the curd. As shown in 

 previous paragraphs, the calcium content of the curd increased 



1 Ramsay. Note on Neutralization of Cream in Butter Manufacture and the 

 Effect on the Butter Produced. New South Wales Dept. Agr., Science Bulletin 

 No. 16, 1915. 



