196 MICRO-ORGANISMS AND FERMENTATION. 



mixed with 68 parts of steamed rice and 72 of water. This 

 pasty mass (" Moto ")' is allowed to remain at about 20 C. ; 

 after some days it clarifies. The conversion of starch and 

 dextrin into sugars progresses, and at the same time a spon- 

 taneous and very violent alcoholic and lactic fermentation 

 sets in. In this fermentation there occurs a Saccharomyces 

 which is able to produce a very high percentage of alcohol .. 

 The mass is now warmed to about 30 C. At the end of two 

 or three weeks the primary fermentation is finished. The 

 product, after being filtered, is subjected to a secondary 

 fermentation, and the liquid is then clear and yellow, like 

 sherry, containing 13 to 14 per cent, of alcohol. It is usually 

 pasteurised at 50-70 C. in iron vessels. 



According to Kellner, Aspergillus Oryzce also plays an. 

 important part in the preparation of Japanese Shoyu or Soja. 

 Saito's exhaustive biological researches into the method of 

 preparation have shown that a koji is used consisting of a 

 growth of the fungus on a mixture of boiled soja beans and 

 parched wheatmeal. The koji is mixed with salt and water 

 at 45 C., and then allowed to ferment, a process which may 

 last a year. The mass gradually acquires a rich reddish- 

 brown colour, and an aromatic odour. It is then placed in 

 small sacks and pressed, an almost clear liquid exuding, 

 which is then further clarified and pasteurised at 50. In 

 this fermentation lactic acid and alcohol are formed, and a 

 number of dissolved aromatic substances. Along with A. 

 Oryzce, Saito found a large number of other organisms taking 

 part in this fermentation, including a new yeast species, 

 Saccharomyces Soya, which is specially active in the production 

 of alcohol. The lactic acid is formed by two bacteria, B. 

 Soya and Sarcina Hamaguchice. According to Kellner, Asper- 

 gillus Oryzce is also of importance in the preparation of the 

 Japanese bean mash (Miso). 



Korschelt found that the hyphae of this species secrete a 

 diastase, which, like malt diastase, converts starch into dextrin 

 and maltose, an observation confirmed by Atkinson, and 

 subsequently by Cohn and Biisgen. 



Atkinson found an enzyme in koji which is soluble in water, 

 inverts cane sugar, and converts maltose, dextrin, and starch- 



