ON DEXTRINE AND DIASTASE. 
279 
Dissolve the diastase in the water, then add the fecula, and 
raise the temperature gradually, stirring the mixture constantly. 
At 150° the whole becomes a mass of thick jelly, which 
liquifies entirely between 150° and 160° Fahr. When this has 
taken place, raise the temperature of the mixture rapidly to 
ebullition, which suspends the action of the diastase on the 
dextrine. Floating through the liquid is seen a floculent sub- 
stance, which is composed of the empty teguments, upon 
which the diastase has no action. After the liquid has cooled, 
filter it, and either precipitate with alcohol, or evaporate care- 
fully to dryness. The advantage of using the alcohol is the se- 
paration of the sugar, which invariably attends the action of 
diastase. 
I think that we may draw from the foregoing exposition 
the following conclusions, viz.: 
1st. That fecula consists of teguments, which envelope a 
peculiar substance of a spongy character, which is either one 
uniform matter, or composed of a soluble and an insoluble 
substance united. 
2d. That dextrine, or gum of fecula, is always a product of 
art, and is derived from the interior substance of fecula, by 
the action of different agents. 
3d. That diastase and sulphuric acid, and other agents, that 
are thought to exercise the power of rupturing the envelopes 
of fecula, do not really possess that power, but the water and 
temperature cause them to be ruptured, and then these agents 
act on the interior substance, and convert it into dextrine and 
sugar of amidon, thus destroying the gelatinous consistence of 
the mixture. 
4th. That diastase is not soluble gluten, as asserted by 
Raspail, but is a substance enjoying the power of converting 
the interior substance of fecula, first into dextrine, and after- 
wards into sugar of amidon. 
