EMILY.
It is, perhaps, for this reason that wine is not obtained from the fermentation of pure sugar; but that fruits are chosen for that purpose, as they contain not only sugar, but likewise the other vegetable ingredients which promote the vinous fermentation, and give the peculiar flavour.
MRS. B.
Certainly. And you must observe also, that the relative quantity of sugar is not the only circumstance to be considered in the choice of vegetable juices for the formation of wine; otherwise the sugar-cane would be best adapted for that purpose. It is rather the manner and proportion in which the sugar is mixed with other vegetable ingredients that influences the production and qualities of wine. And it is found that the juice of the grape not only yields the most considerable proportion of wine, but that it likewise affords it of the most grateful flavour.
EMILY.
I have seen a vintage in Switzerland, and I do not recollect that heat was applied, or water added, to produce the fermentation of the grapes.
MRS. B.
The common temperature of the atmosphere in the cellars in which the juice of the grape is fermented is sufficiently warm for this purpose; and as the juice contains an ample supply of water, there is no occasion for any addition of it. But when fermentation is produced in dry malt, a quantity of water must necessarily be added.
EMILY.
But what are precisely the changes that happen during the vinous fermentation?