Pét-nat – the now widely accepted shorthand for ‘pétillant naturel’ – is a style of sparkling wine that has deep historical roots. It’s thought to be the oldest method of making sparkling wine, pre-dating Champagne, hence its alternative name: méthode ancestrale.
Unlike Champagne, which undergoes two fermentations, the second of which takes place in the bottle to create the fizz, the méthode ancestrale involves bottling the wine before it completes its first fermentation. The process continues in the bottle, capturing the resulting CO2 to produce a bubbly wine.