MOISTURE AND ACIDITY IN CURD, ETC. 51 



milk before adding rennet; (2) low degree of tem- 

 perature in heating curd in whey; (3) removal of 

 whey too soon; (4) any condition that favors the 

 rapid removal of whey and the formation of an 

 excessively dry curd (p. 121). 



EFFECTS OF EXCESSIVE AND DEFICIENT 

 ACIDITY 



Among the more prominent effects to be no- 

 ticed in relation to acidity in curd and cheese, we 

 mention the following: (i) Influence on rennet 

 action; (2) relation to shrinking of curd; (3) ef- 

 fect on expulsion of whey; (4) influence on color 

 of cheese; (5) relation to body of cheese; (6) ef- 

 fect on texture of cheese; (7) influence on flavor 

 of cheese; (8) relation to keeping quality of 

 cheese; and (9) effect on finish or general appear- 

 ance. 



Acidity and rennet action. At the temperature 

 used in cheese-making, rennet -extract coagulates 

 milk-casein only when acids or acid salts are pres- 

 ent (p. 306). The greater the percentage of acidity, 

 up to certain limits, the more rapid is rennet 

 coagulation, other conditions being uniform (p. 



307)- 



Acidity and contraction of curd. The greater 

 the acidity of milk, the more rapid is the contrac- 

 tion of the curd, other conditions being uniform. 

 This is not the same as saying that the contraction 

 is caused by acidity; acidity is probably one of two 

 or more causes, or it may be simply a necessary 

 condition for the continued action of rennet, tem- 

 perature being another important condition for the 



