Pétillant Naturel / Pét-Nat (Ancestral Method, Bottled Mid-Ferment)

Pétillant naturel (pét-nat) is the now widely accepted shorthand for sparkling wine made by the méthode ancestrale, which WSET describes as the oldest way of making sparkling wine. The wine is bottled while still undergoing its first fermentation, trapping carbon dioxide naturally. This is fundamentally different from the traditional method (méthode traditionnelle) used for Champagne, which undergoes two fermentations, the second of which takes place in the bottle to create the fizz. Decanter notes that there is no official definition or legal status for pétillant naturel wines: it is an informal label, and pét-nat can be made from any grape variety, in any region of any country. In Limoux, Benedictine monks are credited with the production of a naturally sparkling wine in 1531, a tradition that Decanter's James Lawther MW says pre-dates that of Champagne. In Gaillac, the appellation text in INAO's 2016 Gaillac file says nobody knows precisely when the first sparkling wines were made, but notes that the Occitan poet Auger Gaillard (1530-1593) described Gaillac wine that sparkled and jumped in the glass. Decanter links the modern category to Loire producer Christian Chaussard, who inadvertently produced a pétillant naturel wine in the early 1990s, after which other Loire producers took up the style. Decanter's William Kelley credits the natural winemakers of the Loire Valley with bringing pét nat onto the wine world stage in the 1990s, citing Agnès and René Mosse as a good example.

• Ancestral method means bottling during the first fermentation, which then finishes in the bottle
• The Gaillac and Bugey-Cerdon rules forbid adding a liqueur de tirage or a liqueur d'expédition
• Pét-nat can be made from any grape variety, in any region of any country (Decanter)
• Several French appellations regulate the method as méthode ancestrale, among them Limoux, Gaillac and Bugey-Cerdon

The winemaker bottles a partially fermented wine while enough sugar remains to generate the carbonation: for Bugey-Cerdon méthode ancestrale, INAO's cahier des charges requires a partially fermented must with at least 40 grams per litre of fermentable sugars (glucose and fructose) at bottling. In Gaillac, according to the appellation text, the grapes are hand-picked and taken whole to the press, and repeated filtrations and natural cold slow the fermentation so that by March there is a clear, partially fermented wine, which is then bottled. Both the Gaillac and Bugey-Cerdon rules state that the fermentation is controlled by cold and by removing part of the yeast population. As temperatures warm in spring, fermentation resumes spontaneously in bottle and creates a natural mousse without any liqueur de tirage; Wine Spectator notes that it ends when the yeast cells deplete the supply of residual sugar. Most pét-nats are bottled using a simple crown cap, like a bottle of beer or a soft drink, although Decanter notes that some use a cork and cage. The spent yeast can stay in the bottle: Decanter's William Kelley writes that pét nat may be disgorged, like a bottle of Champagne, to separate the wine from the dead yeast cells, or left with its sediment. The rules differ by appellation. In Gaillac and Bugey-Cerdon the deposit may be removed by disgorgement or by isobaric filtration, while the Montlouis-sur-Loire cahier des charges requires its single-fermentation sparkling wines to be disgorged, with tirage no earlier than 1 October of the harvest year and disgorgement after at least 9 months.

• Fermentation is slowed by cold before bottling; the Gaillac and Bugey-Cerdon rules add the removal of part of the yeast population, while Montlouis-sur-Loire allows control by cold only
• Crown caps are the usual closure; sparkling wine bottles use thicker, heavier glass to withstand the pressure
• In Gaillac and Bugey-Cerdon, méthode ancestrale bottles must rest at least 2 months on their lees
• Disgorgement is optional: some AOCs require it; many producers leave lees in bottle for a cloudy, textured result

WSET describes ancestral-method wines as typically lightly sparkling, softly textured and fruit-driven, and notes that because fermentation finishes in bottle, pét-nats usually contain lees, giving them a cloudy appearance. Decanter's guide to pét-nat says the bubbles are more gentle than in traditional-method sparkling wines and alcohol levels are generally modest, and that some pét-nats keep a little residual sweetness because fermentation does not always fully finish in the bottle. Style depends on the appellation. INAO's Gaillac text describes méthode ancestrale wines with fine bubbles, an abundant mousse and aromas that can recall apple, characteristic of Mauzac, and INAO describes Limoux méthode ancestrale as developing fruity aromas of ripe apple. Decanter's James Lawther MW describes Blanquette Méthode Ancestrale as a naturally fermented, sweet version with about 7% alcohol and 80 to 90 grams per litre of residual sugar, with more of a baked apple aroma and flavour. The Cerdon name within AOC Bugey is reserved for pink sparkling wines of aromatic type, and its méthode ancestrale wines must contain between 22 and 80 grams per litre of fermentable sugars. Montlouis-sur-Loire's single-fermentation sparkling wines, by contrast, must contain no more than 5 grams per litre, and INAO's text describes an elegant, creamy bubble, with white flowers and white-fleshed fruit.

• Lightly sparkling, softly textured and fruit-driven (WSET)
• Lees usually remain in the bottle, giving a cloudy appearance (WSET)
• Alcohol is generally modest; Blanquette Méthode Ancestrale has about 7% alcohol (Decanter)
• Sweetness varies by appellation: 22 to 80 g/L fermentable sugars for Bugey-Cerdon méthode ancestrale, no more than 5 g/L for Montlouis-sur-Loire's single-fermentation wines (INAO)

Decanter says pét-nat's growth goes hand in hand with the resurgence of the natural wine movement, and that the two share the same philosophy: organic or biodynamic farming, minimal to zero use of sulphur, fermenting with natural yeasts and avoiding fining and filtration. WSET likewise says ancestral-method wines are closely associated with minimal-intervention and natural winemaking. Decanter lists aromatic white varieties such as Riesling and Muscat, grapes that bring good acidity, and juicy red grapes like Gamay as suited to the style. In France, the appellations where this style of winemaking is the norm include Limoux's Blanquette Méthode Ancestrale, Gaillac's Méthode Gaillacoise, Bugey-Cerdon and the Rhône's Clairette de Die Tradition, according to Decanter. In Montlouis-sur-Loire, INAO's text says growers relaunched single-fermentation sparkling wines from the 2000s, describing it as the first method used to obtain sparkling wines. Beyond France, Decanter's William Kelley notes the style gaining traction in North America, with exponents in California (Cruse Wine Company), Maine (Oyster River), Vermont (La Garagista) and New York State (Channing Daughters). In Australia, Tim Wildman MW told Decanter that his first pét-nat, made in the Adelaide Hills in 2014, was one of about five or six Australian versions. Decanter adds that the price point for a pét-nat is often more approachable than Champagne.

• Closely associated with minimal-intervention and natural winemaking (WSET)
• Shared natural-wine practices: organic or biodynamic farming, minimal to zero sulphur, natural yeasts, no fining or filtration (Decanter)
• French strongholds include Limoux, Gaillac, Bugey-Cerdon, Clairette de Die and Montlouis-sur-Loire
• Price point often more approachable than Champagne (Decanter)

Limoux: INAO distinguishes the Blanquette de Limoux sparkling wines, made by a second fermentation in bottle, from the méthode ancestrale wines, which come from a first fermentation completed in bottle; Limoux's sparkling wines were recognised as an appellation in 1938, with the Mauzac grape. The 2016 harvest declaration recorded 5,334 hectolitres of AOC Limoux méthode ancestrale, against 31,414 hectolitres of Blanquette de Limoux and 45,493 hectolitres of Crémant de Limoux, according to a 2017 INAO committee file. Gaillac: according to INAO's 2016 Gaillac file, the first AOC Gaillac decree dates from 1938 and covered sparkling wines made by the méthode ancestrale (known as méthode gaillacoise) or by second fermentation in bottle; méthode ancestrale is made exclusively from Mauzac B and Mauzac Rose Rs, both of which originate in the Gaillac area. Bugey-Cerdon: the Cerdon geographical name within AOC Bugey is reserved for pink sparkling wines of aromatic type from Gamay and Poulsard, and a Cerdon méthode ancestrale cannot be made from Poulsard alone. Montlouis-sur-Loire: Decanter reports that the appellation added Pétillant Originel to its regulations. The cahier des charges modification adopted by INAO's national committee on 18 June 2026 requires the single-fermentation sparkling wines to come from Chenin, from hand-picked grapes carried whole to the press, made without enrichment and without added yeast, and disgorged. Decanter names La Grange Tiphaine's Nouveau Nez as a Montlouis-sur-Loire pét-nat. In North America, Decanter names Cruse Wine Company in California, Oyster River in Maine, La Garagista in Vermont and Channing Daughters in New York State.

• Limoux méthode ancestrale: first fermentation completed in bottle (INAO)
• Gaillac méthode ancestrale (méthode gaillacoise): Mauzac B and Mauzac Rose Rs only, at least 3 bars of overpressure (INAO)
• Bugey-Cerdon méthode ancestrale: pink, from Gamay and Poulsard, 22 to 80 g/L fermentable sugars, at least 3 bars measured at 20°C (INAO)
• Montlouis-sur-Loire: single-fermentation sparkling wines from Chenin must be disgorged and contain no more than 5 g/L of sugars (INAO)

Wine Spectator calls the ancestral method inexpensive but risky and difficult to control. In the traditional method, WSET explains, producers add a measured amount of sugar and yeast and can accurately predict the final alcohol level and pressure in the bottle. The ancestral method, by contrast, bottles the wine before it completes its first fermentation, and the process continues in the bottle (Decanter). Decanter's William Kelley notes that there are often subtle differences in character between bottles, as some finish fermentation with more residual sugar than others. Not disgorging can also have explosive results: Decanter explains that too much sediment or tartrate crystals in the final wine can lead to what is sometimes called gushing, leaving only a third of the liquid in the bottle. Pét-nats are also at risk of the faults that sometimes affect natural wines, such as excessive brettanomyces or volatile acidity, or a mousiness to the flavour. In general, Decanter says, pét-nats are not made for ageing and should be enjoyed young, shortly after bottling.

• Inexpensive but risky and difficult to control (Wine Spectator)
• Bottles can differ, as some finish fermentation with more residual sugar than others (Decanter)
• Too much sediment or tartrate crystals in undisgorged bottles can cause gushing (Decanter)
• Fault risks shared with natural wine: brettanomyces, volatile acidity and mousiness (Decanter)
• Best enjoyed young, shortly after bottling (Decanter)

Primary sources (WSET, INAO, and the Comité Champagne's Champagne.fr): https://www.wsetglobal.com/knowledge-centre/blog/2026/a-guide-to-sparkling-wine-production-methods-and-regional-styles, https://www.wsetglobal.com/knowledge-centre/blog/2023/january/13/what-is-natural-wine, https://www.inao.gouv.fr/produit/limoux-methode-ancestrale-9587, https://extranet.inao.gouv.fr/fichier/PNOCDCBugey.pdf, https://extranet.inao.gouv.fr/fichier/CNAOV-2016-433-Gaillac.pdf, https://extranet.inao.gouv.fr/fichier/6-PNO-CDC-Montlouis-sur-Loire-2026.pdf, https://extranet.inao.gouv.fr/fichier/COMNAT-CST-20210511-1-20170615-NP-CNINAO-exp%C3%A9-MAV-AO-Limoux.pdf, https://www.champagne.fr/en/champagne-frequently-asked-questions. Last verified 2026-09-28