New York Agricultural Experiment Station. 195 



In experiments 55, 56 and 57, the milk was pasteurized at 85° 

 C. (185° F.) and cheese made with and without the use of com- 

 mercial pepsin. 



The details of the conditions of the individual experiments and 

 of the results of chemical analysis are fully given in the 

 Appendix. 



THE RELATION OF RENNET-ENZYME TO CHEESE-RIPENING IN THE 

 ABSENCE OF ACID. 



In experiments 44, 47, 49 and 50, no acid was added and the 

 conditions of experiment prevented the formation of acid, except 

 possibly in minute quantities before the milk was heated. While 

 the conditions of these experiments differ in some details, they 

 were all as nearly alike as possible in respect to the absence of 

 acid. Table I contains the results of chemical analysis when 

 the cheese was fresh from press and when 12 months old. 



Table I. — Showing Effect of Rennet-Enzyme in Cheese-Ripening in 



Absence of Acid. 



If we compare the amount of water-soluble nitrogen com- 

 pounds found in the fresTi cheese and at the end of one year, we 

 see readily that there was little or no advance in the proteolysis 

 taking place in this period of time. It is also significant that 

 there was little, if any, paracasein monolactate formed. The 

 results of these experiments indicate that the rennet-ferment, in 



