Relative Amylolytie Action of Saliva and Diastase of Malt. 131 
The effects, on amylolytic action, of exposing the ferment of saliva to 
different temperatures for varying lengths of time. 
Brown and Heron* state that a malt extract, warmed quickly to 
66° C. and then added at once to starch paste at the same temperature, 
differs but little, in the first stages of its action, from a malt extract 
heated at 60° C.; if, however, the malt extract be warmed for say 10 
or 15 minutes at this temperature, previous to adding it to the starch 
paste, its amylolytic action is very much weakened. Evidently then, 
under the influence of the increased temperature, a portion of the fer- 
ment is destroyed or else changes are induced, by which the action of 
the ferment is modified. Results of like nature were previously 
obtained by O’Sullivan,t with malt extract. 
With saliva, we have tried the following experiments, designed 
originally to throw light on the comparative destructibility of the 
ferment. 
SERIES XJ.—SALIVA. 
The saliva was exposed to the designated temperature for the speci- 
fied time, then added to the starch paste at the same temperature and 
its amylolytic power determined. 
Time of Total amount Starch 
Temperature. exposure, Wt. Cu in 4. reducing bodies. converted. 
60° C, 0 min. 00409 gram, 0°0852 gram. 7°66 per cent. — 
60 15 0°0213 0'0464 417 
60 30 0°0210 0°0460 4:14 
At 60° C. therefore, the coagulating point of albumin and the tem- 
perature at which ptyalin is supposed to be destroyed, it is apparent 
that destruction of the ferment is not complete even by 30 min- 
utes exposure to this temperature. The peculiarity of the results, 
moreover, make it doubtful whether we have to do with destruction 
at all. If the reduced amylolytic action is due to simple destruc- 
tion of the ferment, we should expect less ferment action after 30 
minutes exposure than after 15 minutes; as it is, the action in the two 
cases is the same. A certain time, however, is required to produce 
the change in the character of the ferment. Similar results are 
shown in the following series of experiments, conducted in the same 
manner as the preceding, only at different temperatures. 
* Loe: cit., p. 227. + Loe. cit., p. 143. 
