French term for a type of sparkling wine made by bottling still-fermenting juice and allowing it to finish to dryness in bottle. The carbon dioxide gas created during the finishing step gives the wine effervescence, while the spent yeast cells give it a hazy cast. Some producers choose to disgorge the bottles to purge the wine of this sediment, while others preserve it for the savoryness and texture it imparts.
The literal translation of pétillant naturel is “naturally sparkling,” so-called because the bottle fermentation completes naturally without an addition of sugar and yeast, as required when making champagne.
Often abbreviated pét-nat; synonyms include méthode ancestrale or ancestral method. Col fondo Prosecco is an ancient example of this style.