A fortified wine is a
wine to which additional
alcohol has been added, the most common additive being
brandy (a spirit distilled from wine).The original reason for fortification was to preserve wines, as the higher alcohol level and additional sweetness help to preserve the wine (when supplemental alcohol is added before fermentation finishes, it kills the
yeast and leaves
residual sugar). Even though other preservation methods exist, the fortification process survives, as consumers have developed tastes for wines preserved this way.
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