222 



K. YABK ; ON THE ORIGIN OF 



The conclusion I reached was that the Aspergillus in 

 question is incapable of transformation into yeast cells, and this 

 has been confirmed recently by Klockner and Skionning.'" 



But nor can Atkinsoiis hypothesis be correct; the air 

 could not be the carrier of the yeast germs in the manufacture of 

 sake, as this would imply the frequent occurrence oi sake yeast 

 in the dust of the air of Japan. But my repeated investigations in 

 this direction did not reveal its presence in the air. Thus in the 

 Botanical Gardens at Komaba I once passed 60 liters of air 

 on a bright clear daj- through a flask containing sterilized 

 Pasteur's solution, kept somew hat acid by monopotassium phos- 

 phate. After several weeks mould fungi and yeast cells, besides 

 bacteria, were developed, but among the yeast cells no sake 

 yeast was discovered on further investigation, while much Monilia 

 was observed. 



The air in the /'f?;'/ cellar, however, contained the same yeast 

 which plays the principal role in the fermentation of the sake 

 mash. I exposed a sterile gelatine plate, of a diameter of 9 cm. 

 for 30 minutes to this air and counted, after 76 days' standing at 

 rather low tempei-atures, of colonies of Penicillium 207, 



of Aspergillus 71, 

 of yeast 36. 



This yeast agreed in size, and form, and energy of fermen- 

 tation with sake yeast. How^ did this yeast reach these cellars.? 

 Certainly not through the boiled rice grains which serve to make 

 koji, but through rice straw, which is used in the form of matting 

 for spreading over the koji, and covering it. The following facts 

 confirmed the probability of my supposition. 



1. All the rice sent to the factories is packed in rice-straw, 

 the dust on this straw is thus distributed through the whole factory 



2. The boiled rice is never handled in wooden vessels, but 

 always upon mats made of rice straw. The mats are never made 

 of any other straw. Even the straw of ui)land rice is declared 

 unsuitable hy the manufacturers. 



3. The steamed and cooled rice is rubbed upon these mats 

 by hand, to avoid lumps and separate the grains. 



(OCentralbl. fiir Bact. 1896. During my studies on the development of this 

 Aspergillus under different conditions, I also applied solutions to which small quantities 

 of ferrous sulphate were added, and observed that only in those solutions containiiig|some 

 iron spores were developed, which shows, ia accordance with Molisli, the important 

 influence of this element on fungi 



