What is wine fermentation?
The short answer
Wine fermentation is the process in which yeast converts grape sugars into alcohol and carbon dioxide. In Prosecco DOC spumante, a second fermentation in a sealed tank produces the retained sparkle. The bubbles get noticed, but the first transformation is juice becoming wine.
Answered by Michael Goldstein · Founder, Bella Principessa
Updated on
The full answer
Wine fermentation is the process in which yeast converts grape sugars into alcohol and carbon dioxide. In Prosecco DOC spumante, a second fermentation in a sealed tank produces the retained sparkle. The bubbles get noticed, but the first transformation is juice becoming wine.
A grape is sweet. Wine contains alcohol. Between those familiar facts is fermentation, the process that makes the change possible.
Yeast uses the sugars in grape juice and produces alcohol, carbon dioxide and other compounds that help shape the wine’s character. It is biology doing something you can eventually taste.
Where does the winemaker come in?
The winemaker manages the conditions, including temperature and preparation of the juice, to achieve the intended style. Calling fermentation natural does not mean the wine makes itself without careful attention.
Our first fermentation guide explains Prosecco’s base-wine stage. That wine is the foundation for what happens next.
Why ferment again for sparkling Prosecco?
For Prosecco DOC spumante, the base wine undergoes a further fermentation in a pressure-resistant tank. Carbon dioxide remains in the wine under pressure and is retained through bottling. This is the Martinotti or Charmat method.
Champagne places its sparkling fermentation in bottles. Both depend on fermentation, with different vessels and production sequences. Our Prosecco and Champagne guide puts the difference in context.
What does this tell you about sweetness?
Fermentation explains what happens to sugar, but the finished wine still needs its own sweetness description. Read Brut, Extra Dry or the other term on the label.
Bella Principessa white and rosé Brut give you two different expressions. Our Prosecco sweetness guide explains the category order, including their shared Brut category. Knowing the process helps you understand the wine; knowing the style helps you choose the one you want to pour.
Sources
WSET: sparkling-wine production methods supports the bottle-fermentation comparison.
The long read, in the JournalThe Charmat method: how Prosecco gets its bubbles6 min read →
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