Designation (also abbreviated to Pét Nat) for "naturally sparkling" wines. It is an ancient process, which in France is called Méthode rurale (also Méthode ancestrale). There are no wine law regulations, so the production can be quite different. Unlike a sparkling wine or champagne, there is no "real" bottle fermentation (initiated by adding yeast), but a single fermentation in two steps. After a mash fermentation, which is often spontaneously initiated, the grape must, which has not yet finished fermenting, is bottled at around 20 to g/l residual sugar and 5% alcohol by volume. But this can be done quite differently, so that the fermentation that continues in the bottle can result in a weakly to strongly foaming wine. So whether a semi-sparkling wine or a sparkling wine is produced depends solely on the time of decanting or the residual sugar that is still present. The producer decides whether disgorgement (removal of the yeast) is used. If it is, no dosage or sulphur is usually added. Such products are counted among the group of natural wines. See also under winemaking.
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Fachjournalistin, Lektorin und Verkosterin, Wien