CHAPTER XXV 



Causes of Chemical Changes in Cheese- 



Ripening 



A large amount of work has been done during the 

 past 30 years in connection with different varieties 

 of cheese, in an effort to ascertain what agents cause 

 the changes taking place in cheese during the ripen- 

 ing process. Many of the results have been peculiarly 

 confusing and progress has been slow. Much of this 

 work has been done with the hard types of cheese, 

 the Emmenthaler in Europe and the cheddar in Eng- 

 land and America. The scope of this book does not 

 permit an historical review of these investigations, 

 and the most we can hope to do, within the assigned 

 limits of treatment, is to give a brief summary of 

 what may be regarded as the present state of knowl- 

 edge in respect to the causes of cheese-ripening in 

 the case of cheddar cheese. It is well to preface our 

 discussion with the statement that the amount we 

 actually know at present is disappointingly small, and 

 how much of what we think we know now will be 

 modified by further investigation no one can con- 

 fidently say. In our treatment of the causes of cheese- 

 ripening, we confine our attention mainly to the 

 changes that take place in the protein compounds, 

 which come originally, as we know, from milk-casein ; 

 because, in this portion of the cheese substance, the 

 most profound and extensive changes occur, changes 



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