208 



OKUMURA ; CONTRinUTIONS TO 



itself is made from whitened rice. In whitened rice'" a certain 

 amount of protein is removed with the bran ; so the imperfectly 

 whitened rice may be better suited for the production of the 

 spores of the fungus. The tane-koji was analysed by SatoP The 

 rice is at first steeped in water for 12-18 hours, then steamed for 

 about 2 hours, whereupon it is spread on straw mats. When the 

 temperature has fallen to about 30'C., the rice is mixed with the 

 ash of oak-leaves and the spores of Aspergillus Oryzac. The 

 factories follow the old empirical rule that for about 200 litres 

 of rice four litres of ash and 8 grams of spores are sufficient. In 

 some factories spores are not added, as they abound in the air 

 of the koji room. The rice is then spread in thin layers in open 

 wooden boxes (/{'iyV-<^///^z) about 50 cm. wide, 75 cm. long, 5 cm. 

 deep, and placed in the koji room. After a few days kept at 

 25-30^0. the mycelium is well developed upon the grains, and 

 6-7 days later innumerable spores also.'^' 



The addition of the ash of leaves is intended to accelerate 

 the development of the fungus, and when we remember that the 

 rice grains contain comparatively little ash and that this ash is 

 distributed through the entire mass of the grain, while the fungus 

 develops upon the surface of the grain, the beneficial action of 

 ash will be understood as it contains all mineral matters neces- 

 sary for the fungoid growth. Tane-koji is sold in small bags 

 of 250 g. 



(1) Whitening or cleaning of the rice is separating the bran from the grain. 

 Kclbicr made some researches about this point in conjunction with Tauaka and 

 Kobayashi. (Bulletin I., Xo. 5.) 



(2) We copy from Sato's results the following analyses : — 



Roughly whiiened rice ^ , 

 mi.xed with .ish. 



Crude protein 7-990 8.875 



Ethereal extract 2.072 5.186 



Crude fibre 0.770 1.860 



Starch and non-nitrogenous extract 87.010 59-590 



Dextrin 0.500 J -770 



Glucose... trace. 18.760 



-Maltose — 2.050 



Ash 1.66 1.900 



(3) The tane-koji makers mix some powdered malt with tlie ste.xmed rice. Some- 

 times they also use a certain kind of fungus called iita hoji which attacks the rice fields. 

 According to Prof. Shirais reseaches the ina-koji fungus can produce yeast from its 

 conidia. 



