of Diastase of Malt, as modified by various conditions. 53 
Such a degree of uniformity in the results, makes it evident that 
the slight accelerating action of the acid-proteid is a constant one 
under the above conditions, and indeed all of our results in this 
direction clearly indicate such to be the case. 
Although acid-proteid thus accelerates amylolytic action, it is still 
able under slightly different conditions to retard the action of the 
ferment and even cause destruction; thus by warming the amount 
of ferment (30 c. c. malt extract), used in the preceding experiment, 
at 40° C. for 1 hour with the acid necessary to saturate the proteids, 
in a total volume of 50 c¢.c¢., thus doubling the percentage of acid, 
amylolytic action was found on subsequent neutralization and testing 
with starch paste, to be very much diminished. 'The following results 
obtained with the two malt extracts used in C illustrate this point : 
a. db, C. d. 
Per cent. HC] __ 0 00046 0 0°0046 
ee, =, — — =~ 
Malt extract.... 30c.. a ©, © 30 ¢. c. 30 ae. 
0'1 percent. HCl 0 Zee} Ue 0 2 Si 
[EIN Oars ete 8 ZO lithe: (anes AI ee Weer. 
50°0 ¢. e. 50°0 @. ¢. 50:0 c. e. 50-0 ce. ¢. 
These solutions were warmed at 40° C. for 1 hour, then neutraliz- 
ing and equalizing mixtures were added, after which amylolytic 
action was determined by adding starch paste, diluting to 100 ¢. ¢., 
warming at 40° C. for 30 minutes, ete., with the following results, 
expressed in the percentage of starch converted into sugar. 
a. b. o d. 
Ca 2s rN a i =) 
36°24 21-74 29°25 ; 22°96 
Hence, it is apparent that under these conditions, acid-proteids may 
exert a destructive action on the ferment. This destructive action 
takes place with considerable degree of rapidity, as is shown by the 
following experiment, which at the same time illustrates the acceler- 
ating action of smaller percentages of combined acid and confirms 
the preceding experiments. 
The neutral malt extract required 2°4 c. c. 0°1 per cent. HCl to 
combine with the proteid matter in 30 ¢. ¢. 
Destructive action. Accelerating action. 
SS = = = la = —\ 
ie 2. 3. 4. 5. 
Malt extract_____ B0renc: BON ene: 30 cc. 30 ce. 30 ¢.c 
0-1 per cent. HCl 0 24 * 2:4 0 Q-4. * 
leL(0) “2 See es PAY Wie ss ME Lito ee ce 70O* & Oza 
HONS D0 oe 50 et 100 . 100 
Per cent. HCl... 0 0:0048 0°0048 0 0°0024 
* Containing one gram of starch. 
