320 



Prof. R. W. Atkinson. 



described which will show the rapidity of the action at different tem- 

 peratures and with differing proportions of koji and starch. The first 

 series of experiments was carried ont at the ordinary temperature of 

 the air, which at the time varied between 4° and 10° C. 450 cub. 

 centims. of starch-paste containing 11*43 grms. of dry starch were 

 mixed with 50 cub. ceutims. of hoji extract containing 1*786 grms. 

 of solid matter. The mixture was allowed to stand at this tempera- 

 ture (4—10° C.) with an occasional shaking, and samples were with- 

 drawn at the specified times. After making deductions for the hoji 

 the amount of the starch products was found to be as follows : — 



Table X.— Action of Koji Extract on Starch at 4— 10°C. 

 10 grms. starch to 8*75 grms. koji. 



Time. 



Dry starch 



in 500 

 cub. centims. 



Weight of 

 koji used 



to form the 

 extract. 



Total starch 

 products. 



Specific 

 rotatory . 

 power. 



1 





G-rms. 



Grins. 



G-rms. 



109 C -6 





11 43 



10 



9-714 



120 „ 



35 



j> 



9-904 



100 -2 



192 „ 



55 



55 



10 -369 



90 -4 



240 „ 





55 



10 -450 



80-4 



The course of this reaction is represented graphically in Curve B. 

 The action, comparatively rapid at first, goes on slowly but con- 



Ctjeve B. 



Action of koji extract on starch at 4 3 — 10°. 

















I 



J 





























\ 

 \ 













• 





























\ 



\ 























■ : 













- - 









\ 













1 



■ 







; ' 







■ " 











100° 

















= 









- — 



- — 



:>:; 



— 



























— 



I 



■ 



'■ -V. 







* , 

















50° 















_ 









































: 



























° 1 



5 30 4. 



5 60 



90 1ZO l50 180 2.10 240 hcu.rs ^ 



Time in hours. 



