USE OF MOLDS IX FOOD PRODUCTS 249 



over the surface of the curd, producing an abundant snow-white 

 mycehum. After a time, it may form a Hght green coat of conidia. 

 The ripening process depends upon the proteolytic activities of the 

 organism ; when mature, about 80 per cent of the nitrogenous matter 

 has been made water soluble.^ The ripening begins on the surface 

 and gradually proceeds toward the interior. After the cheese has 

 been properly ripened by P. camemberti, it may undergo rapid spoil- 

 age by a secondary growth of other organisms and so it must be 

 marketed shortly after ripening. The cheese is often packed before 

 it is fully matured, the ripening process being allowed to continue 

 in the container. Cheese of the Brie type is also produced in a man- 

 ner similar to that used for the manufacture of Camembert cheese. 

 A special mold is allowed to develop on the surface of the curd. 



Strains of organisms of the Aspergillus flavus-Oryzae group play 

 important roles in the national economy of the Far Eastern coun- 

 tries, the mold being used in the preparation of many foods. The 

 mold serves the same function in their economy that malt does in the 

 occidental countries. A large number of food preparations used in 

 Japan and China are fermented foods. The conversion of starch to 

 sugars is brought about by the amylolytic enzymes and the proteins 

 hydrolyzed by the proteolytic enzymes of strains of A. flavus-Oryzae. 

 The term koji has been applied by the Japanese to starter. This 

 preparation, generally grown in rice or rice and wheat bran or meal, 

 is a rather mixed culture from which a number of organisms can be 

 obtained. There are several types of koji. Each type is used for 

 a specific product as: sake koji for making rice beer or "wine"; 

 shoyu koji for making shoyu (soy sauce) ; miso koji for making 

 miso, a thick brown paste or porridge; and shochu koji for making 

 shochu (distilled alcoholic drink). Koji is thus applied to a variety 

 of products, made in a number of ways, depending upon its ultimate 

 usage, and from a number of • substances. The predominating or- 

 ganism in the mixed cultures may also vary. It may be prepared 

 by inoculating the steamed rice or wheat bran after cooling with 

 spores of a strain of the A. flavus-Oryzae group. The moist, inocu- 

 lated mass is incubated at 25° to 30° C. for a few hours in a heap 

 until the hyphae of the mold develop. Then it is spread out in 

 shallow layers until the enzymatic (amylolytic and proteolytic) con- 

 tents are at their maxima. During the growth and development of 

 mycelium the moist mass heats considerably so it is occasionally 

 stirred. If the product is not used immediately, it may be dried. 

 Shoyu (soy sauce) is a sauce prepared from soybean. The beans 

 are cooked, mixed with ground, roasted wheat and koji, and allowed 

 to ferment. The mash is allowed to incubate until the sporulating 



