HARD CHEESES. 



223 



made of many shapes, and form, in the end, a very hard, 

 tough cheese, which does not readily undergo putrefaction 

 and which may be preserved for months, becoming more 

 strongly flavored and improving with age. They can be 

 exported readily, and are carried to all parts of the world 

 and form the chief cheeses of commerce. 



FIG. 28. 



A Swiss cheese. A hard variety known as Emmenthaler cheese. 



In making both hard and soft cheeses, ripening is the most 

 essential part of the process. The changes which occur dur- 

 ing the ripening are by no means thoroughly understood. 

 They may be best considered under two heads. 



1 . Changes which increase the solubility of the proteids". 



2. Changes which give rise to flavors. 



