secondary fermentation

Definitions

Wine

  • in the méthode champenoise for making sparkling wine, the fermentation that occurs in the bottle once the dosage (a mixture of sugar, water or wine, and yeast) is added. This creates carbon dioxide as a by-product, which – in the sealed bottle – dissolves in the wine creating the sparkling wine.
  • in making still wine, the second stage of the fermentation process that occurs when the bitter malic acid present in grapes is converted into a less astringent lactic acid, with a by-product of carbon dioxide gas. Almost all red wines include this second stage of fermentation, but producers of white wine often prevent this second stage to ensure that the wine tastes crisp and sharp, although it is also avoided when the grapes are overripe and too sweet.
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