Term (also Pét Nat) for "naturally sparkling" wines. This is an ancient process, which is known in France as the méthode rurale (also known as méthode ancestrale). There are no wine regulations, which means that production can vary. In contrast to sparkling wine or champagne, there is no "real" bottle fermentation (by adding yeast), but rather a single fermentation in two stages.
After a mash fermentation, which is often initiated spontaneously, the unfermented grape must is bottled at around 20 to g/l residual sugar and 5% alcohol by volume. The fermentation that continues in the bottle produces a wine that is slightly to strongly sparkling. Whether a semi-sparkling wine or a sparkling wine is produced depends on the time of decanting and the residual sugar. If disgorgement (yeast removal) is carried out, no dosage or sulphur is usually added. Such products are categorised as natural wines.
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