Agriculture Reference
In-Depth Information
volume occupied by alcohol in a completely fermented
solution will be nearly identical to the volume of sugar that
was in the solution. So if you know how much sugar is in a
solution before fermentation starts, you know how much
alcohol could be produced in a completed fermentation.
As we discussed a bit in the last chapter, what happens over
the process of making wine is a lot more complex than a
simple conversion of sugar into alcohol, so I'd like to expand
on that some more.
Sugar
Unless you are using vitis vinifera grapes, all of your wine
musts will contain less sugar than is needed to make a
self-preserving wine. The sugar content of common fruits
(other than wine grapes) is insufficient. In order for a wine to
be self-preserving without need for pasteurization or the
addition of preservatives, it needs an alcohol content of at
least 9%. In practice, because you may add water between
rackings in order to fill air space, you'll want enough sugar to
yield an alcohol content of 10% or higher.
Measuring Sugar Levels
Many winemaking topics and pamphlets are full of recipes
that specify a certain fixed amount of sugar for a given fruit.
Such recipes rely upon the false assumption that the sugar
content of a given fruit is the same no matter how close to
ripeness it was when harvested, how long it has been stored,
or even the variety of the fruit in question.
