Rennet Tests 



243 



tent it has progressed before the process begins, is 

 exceedingly important to the cheese maker. To this 

 end, several convenient tests may be applied. The 

 veteran, who has attained skill through long manip- 

 ulation, can tell with a fair degree of accuracy 

 through the sense of smell and taste the amount 

 of lactic acid present in his milk, but this is not 

 a safe enough guide for those who are inexpe- 

 rienced, or those who expect to make a uniform 

 product in a uniform 

 way from day to day. 

 Rennet tests. The 

 percentage of lactic 

 acid present in the 

 milk can readily be 

 determined directly by 

 titration with a stand- 

 ard alkali, but the 

 amount of lactic acid 

 present is also quite 

 readily dete r m i n e d 

 by the length of 

 time required for ren- 

 net coagulation, since 

 ren net acts more 

 quickly upon milk 

 the riper it is, and 

 upon this fact two 

 or three simple tests u e b 



have been devised. Fig. 40. Monrad rennet test, a, 5 c. c. pipette; 

 T,, . , n ,-, b, 50 c. c. graduated flask; c, cup in which 



The Simplest Of these test is made. 



