354 Bulletin 257. 



(3) The great majority of acid or sour cheese are caused, not 



by the giving of too much acid, but by not having the 

 curd firmed in the whey when the acid has developed. 



(4) Using large starters. 



How to prevent. 



(i) No sour milk or milk containing more than twenty-six 

 hundredths of one per cent acid should be taken from 

 any patron. 



(2) Add the rennet early enough so that the curd may be firmed 



in the whey by the time the acid has developed sufficiently. 



(3) Do not use too much starter. 



(4) Keep the development of acid under control by controlling 



the moisture. 

 Remedy. 



When it is absolutely necessary to make sour milk into cheese 



it should be done in the following manner: 

 (i) Heat the milk not above 80° Fahr. 



(2) Use an extra amount of rennet. 



(3) Cut the curd into smaller pieces. 



(4) Heat higher. The degree of heat will depend on the rapidity 



with which the acid is developing. Most fast working 

 curds contract rapidly so the heating can be hurried. 



(5) As soon as possible after heating the whey should be run 



down to the level of the curd. This greatly facilitates 

 stirring and firming of the curd, and if more than one vat 

 is being used, time is saved when the remainder of the 

 whey is to be removed. If by this time the curd is not 

 firm and shows too much acid, a sour cheese can be pre- 

 vented by, 



(6) Removing the whey and putting on pure water at a 



temperature of 102° Fahr. The amount of water used 

 and the time it is left on will depend on the amount of 

 acid in the curd. In extreme cases it may be necessary 

 to use a second quantity of water. As soon as the curd 

 becomes firmed in the water and the acid reduced to a 

 normal amount, the water should be removed. The 

 curd should then be treated like an ordinary sweet one. 

 This method is not to be confounded with the "soaked 

 curd" process, which is different. 



(7) If after milling curds are sour, they can be improved by a 



washing in pure water at 80° Fahr. This resembles the 



