ON ALCOHOLIC FERMENTS. 
225 
FERMENT OF BEER. 
8. Essential properties : 
— -Placed in a solution of 
sugar, at a temperature 
varying between 50° and 
84° F., determines a brisk 
fermentation, which ter- 
minates in a few days, not 
being able to be exerted 
in liquors, containing much 
alcohol. Is destroyed in 
the act of brisk fermenta- 
tion. 
9. Collected in ordinary 
beer. 
FERMENT OF DREGS. 
8. Placed in a solu- 
tion of sugar, at a tem- 
perature of from 50° to 
54° F., determines a 
slow fermentation,which 
is complete only after 3 
or 4 months ; it acts in 
liquors containing 16 
per cent, of alcohol. Is 
not sensibly destroyed 
in the act of slow fer- 
mentation. 
9. Collected in very 
strong beer. 
BLACK FERMENT. 
8. Placed in a solu- 
tion of sugar, at a tem- 
perature of from 50° 
to 54° F., determines 
a slow fermentation, 
which is complete only 
after 6 months ; it acts 
in liquors containing 
more than 17 per cent, 
of alcohol. Is not sen- 
sibly destroyed in the 
act of slow fermentation. 
9. Collected in a de- 
posite of white wine. 
The facts contained in this table, says M. Bouchardat, 
show that these alcoholic ferments differ from each other ; 
firstly, in form, color, and dimensions, and in the contents 
of the globules; secondly,, by the mode in which they de- 
compose sugar; thirdly, by the medium in which they 
exist. 
I designate them by the names of beer-yeast, dregs-yeast, 
and black yeast. 
Dregs-yeast and black yeast are especially remarkable, 
because, by aid of a slow fermentation, they can determine 
the formation of richer alcoholic liquors than most generous 
wines. In order to acquire information concerning the na- 
ture of ferments, 1 studied their proximate and elementary 
composition, and the action on these globules of water con- 
taining of hydrochloric acid. 
Proximate Composition of Alcoholic Ferments. 
The following is a list of the substances which enter into 
the composition of ferments: — 
1. ProteYc animal matter, insoluble in alcohol, containing 
nitrogen, hydrogen, carbon, oxygen, sulphur, and phos- 
phorus. 
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