THE WHIPPING QUALITY OF CREAM. 



17 



ACIDITY. 



It has often been noticed that cream which is several hours old will 

 whip better than fresh cream. Because of this it was believed that 

 the small amount of acidity developed in the cream influenced its 

 whipping equality. Also the idea is prevalent that adding a small 

 amount of commercial lactic acid to the cream improves its whip- 

 ping quality. In order to compare the effect of acidity with the 

 effect of age, tests were made on cream representing age without 

 acidity, acidity without age, and both age and acidity. The acidity 

 was obtained both by the natural formation of acid and by adding 

 lactic acid. 



The maximum acidity which cream may contain without acquiring 

 a sour taste is about 0.3 per cent. It was found that increasing the 

 acidity up to and including 0.3 per cent had no effect upon the quality 

 of the whip. (See Fig. 14 and Table 8.) Increasing the acidity in 

 excess of 0.3 per cent caused a slight decrease in the quality of the 



60 

 55 



50 

 -?£ 



4G 

 35 

 30 

 25 

 20 

 /^ 



/o 



■5 



| . B 



J6 



.26 .3 *36 4- &6 .<6 J6 



/=>£/? &£A/t or tfc/0/ry 



.6 .66 .7 .76 



fig. 14. 



-Effect or Increase in acidity on whipping quality of cream. A — B, cream which 

 gives a good whip ; A — C, cream which gives a very poor whip. 



whip until the acidity had increased to such an extent that the 

 cream began to curdle, at which point the whipping quality increases. 

 This was found to be true regardless of whether fresh or aged cream 

 was used 



It. is therefore evident that increasing the acidity of cream will 

 not improve its whipping quality, as it is necessary to increase the 

 acidity to such an extent as to render the cream sour before it will 

 have any effect. 



