MANUFACTURE OF NEUFCHATEL. AND CREAM CHEESE. 13 



various factors which may influence the keeping qualities of the 

 cheese. Very little previous work has been done along this line. 



A study of each of the important steps has -been found nerc ;u 

 to gather definite information with regard to the mosi efficienl -\ - 

 tern of manufacturing, which includes a consideration of three Pac 

 tors: (1) Initial condition of curd; (2) rapidity of drainage; (3) Eal 

 losses. The following subjects have been considered : 



1. Effect of different quantities of rennet. 



2. The use of pepsin as a substitute for rennet. 



3. Effect of temperature on the making process. 



4. Effect of starter on the making process: 



5. Effect of pasteurization and starters on the making process. 



6. Effect of pasteurization on the moisture content of the cheese. 



7. Effect of homogenization on the making process. 



EFFECT OF DIFFERENT QUANTITIES OF RENNET. 



A definite quantity of rennet is necessary in the manufacture of 

 the Neufchatel group of cheeses in order to obtain the characteristic 

 curd, which must be neither too soft nor too brittle. The high cost 

 of rennet requires that the curdling agent be used judiciously. So 

 ' far nothing has been published regarding the most efficient and eco- 

 nomical quantity of rennet to use for these cheeses. The quantity 

 of rennet necessary depends not only upon the- rate at which the 

 whey is expelled, but also upon the breaking up of the curd and 

 upon the fat losses caused thereby. 



To determine this point, commercial liquid rennet in proportions 

 varying from one- fourth of a cubic centimeter to 4 c. c per 100 

 pounds of milk was used, with the results shown in Table 1. In 

 each case 250 c. c. of lactic starter was added to each 30-pound unit 

 of milk. Thirty pounds of milk was used in each of the experiments. 

 All the whey was collected and measured from the time the coagulum 

 was poured upon the draining cloths until the curd was in fit condi- 

 tion to ice, or in some cases for only part of that time. In any case 

 the different parts of each sample were handled in the same manner. 

 Fat determinations were made of each unit of a sample. 



It is noticeable that the losses of fat increase with the higher per- 

 centages of fat- in the milk, and there is also a slight increase in 

 losses with the higher proportions of rennet. The losses of fat in the 

 whey appear to be greatest when the large quantity of rennet causes 

 the coagulum to be so brittle that it appears to break up more readily 

 than when the lower proportion of rennet is used. Rennet in as 

 small quantities as one-half of a cubic centimeter gave fairly satis- 

 factory results with Neufchatel cheese, though the curd of cream 

 cheese appeared somewhat too moist. When 3 or i c. c. of rennet per 



