200 THE BOOK OF CHEESE 



However, it is better to gauge the heat so that the water 

 may be left, as this helps to hold the curd at an even 

 temperature, especially in cold weather. In a steam- 

 heated vat there is not so much danger of the tempera- 

 ture running up. 



The stirring must be kept up after the steam has been 

 turned off until the curd has reached such a stage of 

 contraction that it will not readily pack or mat in the 

 bottom of the vat. After the curd reaches this stage it 

 may be allowed to settle to the bottom and stirred only 

 occasionally until it is time to remove the whey. If the 

 cheese room is not warm and there is danger of the curd 

 cooling, a cover should be placed on the vat. The curd 

 should not be allowed to settle for more than fifteen 

 minutes without stirring to keep each piece separate. 

 This is necessary to obtain uniform contraction of all 

 curd masses. 



198. Removing the whey. To permit the normal 

 changes in the curd to take place naturally, two and one- 

 half hours from the time the rennet extract is added is 

 ordinarily required before the whey is drawn. The time 

 of removing the whey is determined by two factors : one, 

 the acid development, and the other, th*e firmness of the 

 curd. For the best results, it is better to have the firmness 

 of the curd a trifle ahead of the acid development. When 

 the proper acid development has been reached, the whey 

 must be removed, regardless of the firmness of the curd. 

 If the curd has not become firm enough by natural forces, 

 when the acid development has reached the proper stage 

 to remove the whey, it must be firmed by other means. 

 If it is not firm enough, either by natural or artificial 

 means, when the whey is removed, a sour cheese is 

 the result. The acid development should not be al- 



