622 MILK 



in the culture. Before soaking the mats should be boiled and 

 dried at high temperature (70 to 80 C.). After soaking in the 

 milk culture for half an hour the mats are placed in the ripening 

 cellar and the surface smeared with moldy cheese. The red cocci 

 multiply rapidly and soon break through the layer of cheese. The 

 curd which now contains lactic acid bacteria, yeasts, molds, and 

 Oidium lactis is placed on the mats and the ripening process pro- 

 gresses rapidly. The balance of the milk culture of micrococci is 

 sprinkled on the walls of the cellar. 



In this country Thorn has given much time to the study of 

 Camembert cheese. He describes the stages of ripening as fol- 

 lows: First two weeks: Cheeses enter the ripening room on the 

 third day after making. They usually become sticky, with evi- 

 dence of Oidium lactis, and often with the smell of yeast, within 

 three or four days. In five or six days threads of Camembert 

 mold appear. In nine to twelve days the colonies of Camembert 

 mold show traces of colored spores. The colonies of the Camem- 

 bert mold appear as patches on the side or edges or as a light 

 covering well distributed, but they should not form a heavy felt 

 all over. Uncovered areas should show a marked slimy, reddish 

 covering. If the room is too wet, oidium, yeast, bacteria, and 

 mucor may displace the Camembert mold. Soon in normal 

 ripening the slime-forming organisms are covered by the my- 

 celium of the Camembert mold. This mold extracts water from 

 the surface and the rind becomes too dry for the slime-forming 

 bacteria. At the end of two weeks' ripening the rind of the 

 cheese should be well established and the first traces of softening 

 appear. If the rooms are kept cold every stage of ripening may 

 require double the amount of time needed at 52 to 56 or 58 C. 

 Cheeses low in water content require more time than those with 

 high percentages of water. 



Third week: During the first two weeks little or no change in 

 the sour curd is noticeable. A piece of litmus paper pressed against 

 the cut cheese will show an acid reaction, although surface layers 

 for perhaps J inch may test alkaline. Ripening proceeds more 

 rapidly during the third week, and the curd just below the rind 

 softens. The line between the sour and ripened curd is a fairly 

 sharp one, as shown by the softening of the texture. Ripe cheese 

 is usually neutral or alkaline to litmus, although occasionally it 

 may be acid. 



When this softening becomes noticeable at the edges of the 

 cheeses they must be removed from the matting, otherwise the 

 rind may peel off and adhere to the matting. They are then 

 placed on ripening boards and turned once a day to secure uni- 

 formity of ripening. The time required depends largely upon the 



