SOFT CHEESES. 



2 3 I 



The importance of microorganisms in cheese ripening may 

 be illustrated by a brief description of the method of manu- 

 facture of the Roquefort cheese (Fig. 27, i). This familiar 

 cheese is filled with green spots, and the peculiar piquant 

 taste of the cheese is associated with these green masses. A 

 microscopic study shows that these green spots are chiefly 

 spores of a common species of mold (Penicillium glaucum, 

 Fig. i ) , the species perhaps being identical with the common 

 blue mold that grows on bread. The method of manu- 

 facture of Roquefort cheese is designed to stimulate the 

 growth of these molds. The first step in its manufacture 

 is to place slices of bread upon shelves in a damp, musty 

 room, and leave them until they have become completely 

 overgrown with a dense mass of mold. The moldy masses 

 of bread are then dried and subsequently ground into a 



FIG. 29. 



Stilton cheese. 



powder. In making the cheese, after precipitating the curd 

 by means of rennet, it is mixed with a considerable quantity 

 of this ground, moldy, bread powder and set aside to ripen. 

 In order to facilitate the growth of the molds oxygen is 



