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MANUAL OF MILK PRODUCTS 



particles of curd, it is ready for cutting. Publow gives the 

 following rule as perhaps the most accurate one for determining 

 when the curd is ready to cut : 



"Two and one half times the period from adding rennet till 

 the first thickening appears gives the time for cutting." 

 Method of cutting the curd. 



It is important that the curd be cut into pieces of uniform 



size in order to insure their even contraction and expulsion of 



whey. This process is accomplished by 



the use of gang knives made either of steel 



or fine wire (see Fig. 54) . 



First the curd should be cut lengthwise 

 of the vat by the use of the horizontal 

 knife. This cuts it into slices or layers 

 one-half inch thick. Next it should be 

 cut crosswise of the vat with a perpen- 

 dicular wire knife and, finally, cut length- 

 wise, using the same perpendicular knife. 

 This combined cutting leaves the curd in 

 small cubes with straight sides. In using 

 the knives, great care should be taken not 

 to break the curd, since this will permit 

 the escape of the fat globules, and a larger 

 percentage of fat will be lost in the whey. The more carefully 

 the cutting is done, the smaller will be the loss of fat. In using 

 the knives, they should be moved slowly and, in passing them 

 through the vat, care should be taken to follow accurately the 

 line of the last cutting, carelessness in cutting being sure to 

 result in increased losses in fat and yield. Sometimes the 

 cheese-maker may wish to vary the size of the cubes of curd in 

 order to influence the expulsion of the whey and the control of 

 the moisture. As soon as the curd has been cut, the whey 

 begins to escape, the little cubes contract in size, and a thin 

 film forms on the face of the cubes. After the curd has been 



Fig. 54. — Wire 

 knives for cutting the 

 curd. 



