20 
RESEARCHES ON THE MANUFACTURE, 
II. Milk sugar. The mixture consisted of 200 c.e. of a 
solution of milk sugar and 100 c.c. of koji extract, and was 
heated to 40-45° C. for 21 hours. The following rotations were 
observed : 
Solution of milk sugar. 12.7° 
Extract of koji, fresh. 10.3° 
,, „ ,, after heating . 9.9° 
Mixture after heating. 11.9° 
Before the mixture was warmed, it had, according to the 
preceding figures, a rotatory power of 11.8°, which almost 
exactly coincides with the rotation actually observed after 
the koji had been allowed to act on the sugar. The experi¬ 
ment consequently shows, that milk sugar is not acted on by 
the ferment of koji. 
III. Maltose. This experiment was carried out with the 
same proportions of sugar solution and koji extract as that 
with milk sugar. The optical rotations observed were, as 
follows : 
Solution of maltose . 13.0° 
Extract of koji, fresh . 10.3° 
„ ,, ,, after heating . 9.9° 
Mixture after heating. 8.4° 
The original maltose solution contained 4.7 %, which 
amount was reduced by the dilution with koji extract to 
3.134 %, equal to 8. 67° Wild. After the action of the fer¬ 
ment this rotation proved to be diminished to 5.1°. Asa 
solution of maltose of 100° AA r ild yields, after the complete 
conversion into dextrose, only a rotation of 42.2°, the result 
of the experiment shows that a considerable proportion of 
maltose had been changed by the ferment of koji into dex¬ 
trose. A calculation similar to that given in detail in the 
description of the experiment with cane sugar shows that the 
solution (koji extract deducted) contained after heating : 
0.80 % of maltose = 2.5° Wild and 
2.46 ,, „ dextrose = 2.6° „ 
3-26 % „ 
5.1° 
sugars 
