CHEMICAL CHANGES IX RIPENING 



351 



depends upon the conditions of ripening. For ex- 

 ample, at low temperatures, the transient protein 

 products formed appear to pass into other forms less 

 rapidly than at higher temperatures, and they tend to 

 accumulate to some extent. This can be shown by 

 comparing the results secured with cheeses ripened at 

 2,2° F. and at 70° F. 



Age 



of 



cheese 



Percentage of ni- 

 trogen in form of 

 paranuclein in 

 cheese at 



Percentage of ni- 

 trogen in form of 

 caseoses in 

 cheese at 



Percentage of ni- 

 trogen in form of 

 peptones in 

 cheese at 



70°F. 



Months 



li 

 3 



6 

 9 



12 

 18 



Per cent 

 6.81 

 5.45 

 3.67 



3.51 

 1.50 



Now, quite different from the behavior of these 

 compounds is that of amino acids, which appear be- 

 yond question to be formed from the peptones, and 

 of ammonia, which is formed from the decomposition 

 of amino acids. Ammonia is an end-product and the 

 amino acids are end-products to a considerable extent 

 in cheese normally ripened. They therefore accum- 

 ulate in increasing quantities under all conditions 

 that favor their formation. 



INFLUENCE OF PRODUCTS OF CHEMICAI, 

 CHANGE IN THE CHEESE-RIPENING 



PROCESS 



Attention has been called to the fact that chemi- 

 cal changes in the proteins of cheese take place 



