Champagne Method
Champagne is a sparkling wine made using the traditional method, which is the most labour-intensive process. The second fermentation happens inside the bottle, with a minimum lees-aging (where the sediment is left in the bottle) duration. Lees are removed by sitting the bottle upside down and freezing it to force the sediment out when uncapped before a mixture of sugar, and wine is added, and the bottle is corked. This process creates richness and complexity.
Charmat Method
Charmat sparkling wine is less expensive to produce compared to Champagne. With the Charmat method, secondary fermentation happens in tanks. Fermentation stops when the winemaker cools the tank, after which the wine is filtered and bottled. This method enhances clean fruit aromatics to create easy-drinking wine, often used for Processo.
Ancestral Method
The Ancestral method of making sparkling wine is what's used today to create pet-nat. Instead of creating a secondary fermentation, the first fermentation is allowed to continue in the bottle, resulting in a cloudy, earthy, textured wine.