The ancestral method, or méthode ancestrale, is a way of making sparkling wine in which fermentation continues in bottle and the carbon dioxide made by fermentation becomes the bubbles. It is closely related to contemporary pét-nat, but the two terms are not always identical. If you are mainly deciding what to drink, start with our guide to choosing pét-nat wines; this page explains the method itself.
How the ancestral method works
In broad terms, the ancestral method begins with a fermenting wine that has not yet used up all of its fermentable sugar. The producer bottles it while fermentation can still continue, seals the bottle, and allows the remaining fermentation to create carbon dioxide inside the bottle.
That is the shared principle. The details vary: grape variety, temperature control, timing of bottling, sediment handling, pressure, sweetness and disgorgement are all producer choices or appellation choices. A historic Bugey Cerdon, a contemporary Loire pét-nat and an Italian col fondo can all involve fermentation or refermentation in bottle, but they belong to different regional and production traditions. Cerdon, for example, stops fermentation by chilling and allows it to resume in bottle.
Fermentation in bottle
Fermentation converts grape sugar into alcohol and carbon dioxide. In still wine, most carbon dioxide escapes. In ancestral-method sparkling wine, the bottle is sealed while fermentation can continue, so the gas is retained and dissolves into the wine.
Technical terminology can be confusing here. In everyday winemaking language, the ancestral method is usually described as one fermentation that begins before bottling and continues in the bottle. The OIV uses ‘secondary fermentation’ more broadly for alcoholic fermentation in a sealed container, including fermentation of partially fermented must. That broad definition should not be confused with the traditional method’s separately initiated bottle fermentation using tirage.
Lees, sediment and cloudiness
Lees are the spent yeast and fine particles left after fermentation. In bottle-fermented sparkling wine, lees can contribute texture, savoury notes and a cloudy appearance if they remain in the bottle.
Cloudiness is therefore common in ancestral-method wines, but it is not automatic. A producer may leave the lees in place, allow them to settle, disgorge the bottle, or use other cellar choices to present a clearer wine. A cloudy bottle is not automatically faulty; a clear bottle is not automatically less authentic.
Disgorged and undisgorged wines
Disgorgement is the removal of sediment collected near the closure. In traditional-method Champagne production, riddling gradually moves sediment into the bottle neck before disgorgement. In ancestral-method and pét-nat production, some producers use disgorgement and some do not.
Undisgorged wines may pour with more sediment and texture. Disgorged wines contain less sediment and usually look clearer. Neither choice is inherently superior. The right preference depends on the wine, the producer's intention and how you like to drink it.
Pressure and bubble style
Pressure varies. Some ancestral-method wines are lightly sparkling and gentle; others are more foamy and energetic. OIV's formal sparkling-wine definitions use pressure and sugar categories, but not every bottle sold informally as pét-nat is trying to behave like a full-pressure traditional-method sparkling wine.
This is why blanket rules can mislead. A crown-capped, cloudy, low-pressure wine and a clearer bottle-fermented sparkling wine may both be connected to the ancestral-method family, yet they can feel very different in the glass.
Unless a producer gives a precise pressure figure, it is more useful to think about the drinking experience: gently spritzy, softly sparkling or more fully sparkling. Terms such as sparkling, semi-sparkling, frizzante and pétillant can also carry legal or regional meanings, so they should not be treated as one universal scale.
Stability and bottle variation
Because ancestral-method wines are often bottled before fermentation is fully complete, timing and control matter. Good producers manage this carefully. Variation between bottles can happen, especially with wines bottled with sediment and minimal additions, but instability and faults are not virtues in themselves.
The best examples feel alive without being careless: fresh, balanced, clean enough to enjoy, and expressive of their grapes and place.
How does it differ from the traditional method?
The traditional method usually starts with a finished base wine. A tirage mixture of sugar and yeast is added before bottling, which triggers a second fermentation in bottle. The wine then ages on lees, is riddled to gather sediment, disgorged, and may receive dosage before final closure.
The ancestral method normally relies on sugar already present in the still-fermenting wine, rather than restarting a completed base wine with tirage. That is the key distinction. Both can involve bottle fermentation and lees, but the timing and cellar logic are different.
How does it differ from Charmat or Martinotti?
Charmat, also called the Martinotti method, carries out the bubble-forming second fermentation under pressure in a tank rather than in each final bottle. Prosecco DOC describes this as the natural secondary fermentation of base wine in large autoclaves.
That differs from the ancestral method, where fermentation continues in bottle from sugar already present in the fermenting wine. The methods differ in where the effervescence is created and how lees and sediment are handled; flavour and texture still depend on the individual wine and producer.
Is every ancestral-method wine pét-nat?
Not necessarily. Pét-nat is the contemporary shorthand most drinkers recognise, while méthode ancestrale is the technical and historical term. Many pét-nats are ancestral-method wines, but not every historic or appellation-based ancestral-method wine is marketed as pét-nat, and not every bottle-fermented sparkling wine should be called pét-nat.
Bugey Cerdon is a useful example because the appellation has its own regional identity and uses méthode ancestrale language. Italian col fondo wines also show how bottle refermentation and retained sediment can belong to local traditions that overlap with, but are not identical to, today's pét-nat culture.
Examples at Cave
These bottles show how related bottle-fermentation traditions appear in different regions. Malibran Sottoriva Col Fondo is useful for understanding bottle-fermented, sediment-friendly Italian fizz, with more background on Malibran. Philippe Balivet Bugey Cerdon Méthode Ancestrale connects the method to a recognised French regional style, with producer context on Philippe Balivet.
Accadia In Fermento is another Cave example that also provides a bridge back to contemporary pét-nat. For shopping rather than technical reading, use the Sparkling Wine collection.