300 



Prof. R. W. Atkinson. 



Section IV. — Change which the Bice Grain Undergoes by the Growth of 



the Fungus. 



It is shown by a comparison of the analyses of rice and hoji that 

 the principal change which is to be observed is the conversion of the 

 insoluble albuminoids of rice into the soluble state, and, probably as a 

 result of. this, the large increase in the total soluble solid matter. 



It may be desirable before entering upon the preparation and 

 properties of the substance which the Japanese call hoji, to mention 

 briefly the uses to which it is put in this country. It is universally 

 employed as a fermenting agent, but it is something differing from 

 such a body as " barm or yeast," by which Dr. Hepburn translates hoji 

 in his invaluable dictionary. Its principal use is in the production of 

 sake, the alcoholic liquid which is everywhere consumed in Japan. 

 This liquid is prepared from steamed rice by digestion with hoji, the 

 diastase of which effects the conversion of the starch into matter 

 capable of being fermented. 



Another use to which hoji is applied is in bread -making. It is also 

 employed in the manufacture of the famous sauce " Soy," which is 

 likewise a product of fermentation, though its preparation is much 

 more complicated, and has not yet received an explanation. 



In ''Nature" (September 10th, 1878), I gave a very brief account 

 of the mode of producing sake, and about the same time Mr. 0. 

 Korschelt read a paper before the German Asiatic Society of Japan 

 giving a detailed description of the process, together with some experi- 

 ments upon the action of water upon hoji. The result of his investi- 

 gation was that hoji acted as a kind of diastase, converting starch into 

 sugar, but he gave no experiments which could serve to identify the 

 product. 



In a paper read before the Chemical Society in March, 1880, of 

 which an abstract appears in the " Chemical News," April 9th, 1880, 

 I gave a series of analyses of the mash, as the result of which the 

 conclusion was drawn that the diastase of hoji, unlike that of malt, 

 yields dextrose and dextrin when it acts upon gelatinised starch. The 

 conclusion was correct as referring to the ultimate products, but 

 further experience has shown that the first product is not dextrose, but 

 maltose, which, however, is quickly hydrated to dextrose. Evidence 

 of this will be found in a later part of this paper. 



I. — Preparation of the Koji. 



The rice grain consists of several envelopes, the outer of which are 

 easily removed in the form of chaff by threshing, and after being 

 burnt, the mineral constituents are returned to the soil. The grain 



