310 



Prof. R. W. Atkinson. 



has not remained the same. This will be better seen by calculating the 

 amount of dextrine, albuminoids, and dextrose from the specific 

 rotatory power, assuming that of the albuminoids to be — 40°, an 

 assumption which, if not quite accurate, will, however, not materially 

 influence the results. 



Table VI. — Composition of the Solid Matter in Solution.* 





Dextrose 



Dextrin 



Albuminoids 





per cent. 



per cent. 



per cent. 



18 hours at 10—12° C. . . . . 



69 -3 



14-7 



16-0 



i hour at 45° C 



84 -9 



12 5 



2-6 





68-5 



10 -o 



21 5 



It is evident that the percentage of dextrine is smaller when th . 

 digestion is carried on at a higher temperature, but that relatively t * 

 the amount of dextrose it has not altered within the time limits of 

 the experiments at 45° C. will be best seen by calculating the amount. : > 

 of dextrine and albuminoids per 100 parts of dextrose. 



Table VII. — Amounts of Dextrin and Albuminoids per 100 of 



Dextrose. 



Dextrin. Albuminoids. 



11 hours at 10-12° C. . . 21 2 .... 23 '1 



1 hour at 45° C. 14 7 .... 3 '06 



2 hours at 45° C 14 '6 .... 25 '3 



The amount of albuminoids dissolved out after half an hour's digestion 

 at 45° C. is only about one-eighth of the quantity dissolved after two 

 hours. This bears out the observations made with respect to the cold 

 solutions of koji, viz., that the longer the time of digestion the greater 

 was the amount of albuminoids dissolved. It may reasonably be in- 

 ferred from this that the albuminoids, as they exist in koji, are not in 

 a soluble form, or not so to any great amount ; but by the growth of 

 the fungus the albuminoids of the rice have been brought into such a 

 state that they are easily degraded by the action of water and rendered 

 soluble. 



The action of heat upon the cold water extract is not very marked 



* Calculated thus : — 



k = gvm. of glucose in 1 grm. solid matter; 

 a? = grm. dextrine; 

 1 — {x + h) =grm. albuminoids ; 

 p = observed specific rotatory power. 

 p = 216.r + 59& — 40|1— x — k), from which x, the unknown quantity, is found. 



