34 SCIENCE AND PRACTICE OF CHEESE-MAKING 



are then turned every 15 minutes until the opera^ 

 tion is completed. After a while the strips may be 

 piled in deeper layers. The repiling is performed 

 again and again, always exposing to the air the 

 portions that were turned inside on the previous 

 piling, in order to keep the temperature uniform 

 through the mass. The operation is hastened by 

 piling the strips two or three layers deep. If the 

 curd is very moist and the formation of acid goes 

 on quickly, it is not advisable to pile the blocks in 

 deep layers. It is better to separate them so that 

 they will dry out as soon as possible. 



Object of cheddaring operation. — The object of 

 the cheddaring operation is to accomplish two re- 

 sults : ( I ) The formation of a curd containing less 

 water by the removal of whey; and (2) the forma- 

 tion of a characteristic body and texture in the 

 curd. The physical condition of the curd changes 

 from a tough, rubber-like consistency with a high 

 water content to a mass having a smooth, velvety 

 appearance and feeling, and a softer, somewhat 

 plastic consistency. The texture also changes so 

 that the curd acquires a peculiar fibrous condition 

 or grain, tearing off somewhat like the cooked 

 meat of a chicken's breast. Along with these 

 changes the curd forms longer strings on a hot 

 iron, usually an inch or more after the cheddaring 

 has continued for some time. Some chemical 

 changes appear to take place in the proteins. The 

 changes noted above are due to the formation of a 

 substance in the curd which is dissolved in warm, 

 5 per cent brine (p. 147). This substance in pure 



