🍷 Pét-nat

Pét-nat (pétillant naturel) is a sparkling wine made by the ancestral method (méthode ancestrale). In French ministry terms, the gas in the wine comes from the fermentation of the grape's own sugars, unlike the traditional method, where the gas comes from sugar added for a second fermentation.

The ministry's 2010 reply to a parliamentary question says that no regulation governs the mention "méthode ancestrale" except the specifications of four appellations: Limoux, Gaillac, Cerdon and Clairette de Die. Pét-nat itself has no legal definition.

The specification of AOC Bugey (September 2025 edition) shows how strict the rules can be for Bugey-Cerdon, a rosé sparkling wine always labelled "méthode ancestrale". It is made from Gamay and Poulsard (not Poulsard alone) from partially fermented must with at least 40 g/l of fermentable sugar at bottling. Fermentation is slowed by cold and by removing part of the yeast, and a liqueur de tirage and a liqueur d'expédition are both forbidden. The wine stays at least two months in the bottle on its lees.

The finished wine must have 22 to 80 g/l of fermentable sugars, an overpressure of at least 3 bar at 20 °C and at least 6.5 % acquired alcohol. The specification describes it as generally 7 % to 9 %, with a fine abundant foam and red-fruit aromas.