CHEESE 623 



temperature at which the cheese is ripened. At about 60° F. 

 cheese ripens almost completely in twenty-one to twenty-four 

 days, while at 50° to 54° F. it may take twice as long. Cheeses 

 ripened rapidly decay rapidly. Cheese which has ripened for a 

 long period retains its condition for a long time. Usually after 

 three weeks of ripening the cheeses are wrapped in parch- 

 ment paper or tinfoil and placed in boxes. Tinfoil wrapping 

 prevents evaporation, hastens ripening, produces a more liquid 

 cheese, and leads to strong odors and flavors. Fully ripe cheese 

 is of the consistency of moderately soft butter or may be soft 

 enough to run. The cheeses are sent to the market when ripen- 

 ing has progressed to a stage where softening extends about i 

 inch from the surface. Ripening is finished in cellars of dealers or 

 those of hotels or caf&. 



The ripening agents, according to Thom, are Penicillium cam- 

 emberti, or its white form P. camemberti var. rogeri, Oidium lac- 

 tis, and species of bacteria which, with Oidium lactis, take up the 

 reddish slime. The properties of Camembert cheese are due to 

 complex chemical changes of the casein, while the fat is little 

 affected. The Camembert mold causes the changes in texture, 

 while Oidium lactis and the red slime-forming bacteria produce 

 the flavor. Therefore the presence of red slime on a cheese is a 

 criterion of a good quaHty. 



A bluish-green layer on Camembert cheese indicates either 

 contamination with a green penicilUum or an overproduction of 

 spores of the Camembert mold. In both cases the cheese is of 

 poor quahty. 



Roquefort cheese is harder than Camembert cheese, but not 

 as hard as Emmenthaler or Cheddar cheese. Ripening of Roque- 

 fort cheese is due to the action of lactic acid bacteria and a green 

 penicillium which has been thought to be identical with P. glau- 

 cum, the common green mold. It seems, however, that the Roque- 

 fort cheese mold is a variety closely related to P. glaucum. The 

 acid curd is placed in caves which have been used for ripening the 

 cheese, and many fine holes are punched into the curd by means 

 of a special instrument. The Roquefort mold spores enter these 

 holes and ripening begins. The holes also serve the purpose of 

 admitting air which is needed for growth of the mold. The 

 curd may be mixed with moldy bread which has been dried and 

 pulverized. Ripening is very uniform throughout the cheese. 

 The texture is soft and crumbly and the taste peculiarly sharp. 

 Roquefort cheese is most commonly prepared from sheep's or 

 goat's milk, but cow's milk is also used. The characteristic green 

 marble-like appearance of the cheese is due to colonies of the 

 mold. Gorgonzola, Stilton, and Brinsen cheeses are similar to 



