30 
RESEARCHES ON THE MANUFACTURE, 
1) Koji alone . 
Contents of 
lactic acid, 
°/ 
' O 
Optical 
rotation, 
0 \Y i M. 
2.05 
Cane sugar 
inverted 
while heating. 
Relative effect 
of the ferment 
on cane sugar 10. 
2) „ +acid. 
.0.5 
1.55 
— 
— 
3) Cane sugar alone 
. 0 
6.85 
— 
— 
4) „ „ + acid 
.2 0 
6.8 
0 
— 
5) „ „ + koji 
. 0 
5.5 
1.94 
100 
G) Cane sugar + 
+ acid. 
koj, Jo.05 
4.6 
2.46 
127 
7) „ . 
.0.10 
6.3 
1.485 
77 
8) „ . 
.0.20 
7.8 
0.63 
32 
9) „ . 
.0.30 
7.9 
0.56 
29 
10) „ . 
.0.40 
8.2 
0.40 
'.21 
11) „ . 
.0.50 
8.2 
0.40 
21 
12) „ . 
.0.60 
8.3 
0.34 
18 
13) „ . 
.0.60 
8.4 
0.29 
15 
14) „ . 
.0.80 
8.5 
0.23 
12 
15) Lactic acid. 
0 
— 
— 
As the lactic acicl alone was found to be optically inactive 
and as it also did not invert any trace of cane sugar (trial 3 
and 4), we must conclude from the gradual diminution of the 
inversion observed in trials 7-14 that the lactic acid, when 
present in quantities of 0.1 % and more., gradually diminishes 
the inverting power of the invertase. In trial 6, the propor¬ 
tion of 0.05 % of lactic acid makes an exception, it favours 
the action of the ferment, a fact which need cause no surprise, 
as a similar amylolytic ferment, the diastase of malt exhibits 
according to Kjeldahl” the same deportment, being almost 
inactive in neutral solutions but displaying the strongest 
action in slightly acid fluids and suspending entirely its sac¬ 
charifying power in the presence of large proportions of acid. 
The figures (in the last column of the above table) showing 
the relative effect of invertase on acid cane sugar solutions 
10 Fourni by setting tbe quantity of inverted sugar in trial 5 as equal to 100 
and caleulalingjthe corresponding amounts on this basis. 
11 M. Mærckcr, Handbuch der Spiritusfabrikation, 1880, p. 37. 
