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!dANUFAafURING AND ADULTERATING LIQUORS.
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solutions that spontaneously run into the state offer–
mentation, the ferment is supplied by nature, and is
intimately associated with the saccharine matter. In
suchcases, the nitrogenous matters present are thefirst
to suffer decomposition or fermentation; and this par–
ticular motion of their atoms is communicated to the
sugar, and continues till the latter has entirely disap–
peared from the liquid, or the former is wholly pre–
cipitated in the shape of decomposed yeast or fer–
ment.
In
those vegetable solutions which scarcely
pass into the state of fermentation, or among whose
molecules such changes progress slowly and irregu–
larly, there is a deficiency of nitrogenized matters or
exciters of fermentation, and it becomes necessary
to add a ferment. Recently expressed grape-juice
(must) offers a lively instance of the former class of
substances; and infusion of malt (wort) of' the latter.
When grapes are squeezed in the air, the limpid juice
soon manifests the usual symptoms of fermentation,
the liquid becomes turbid, carbonic acid gas is de–
veloped, and the
nit~ogenized
principles which the
juice previously contained are decomposed and pre–
cipitated under the form of ferment, which immedi–
ately induces the decomposition of the sugar ; and
this state continues until the whole of' the yeast is
precipitated in an insoluble and inert form, or the
whole of the sugar is decomposed.
In
the juice of
Digitized
by