What is the term used for the fermentation that takes place after a base wine is bottled in sparkling wine production?

In sparkling wine production, the term used for the fermentation that occurs after the base wine is bottled is known as secondary fermentation. This process is critical in producing the carbonation that characterizes sparkling wines, such as Champagne. During secondary fermentation, sugar and yeast are added to the base wine before it is sealed in the bottle. The yeast ferments the added sugar, producing carbon dioxide, which is trapped in the sealed bottle, leading to the formation of bubbles. This method is essential for developing the desired effervescence and enhancing the complexity of flavors in the wine.

Primary fermentation occurs before bottling, in which the initial fermentation transforms grape juice into wine. Malolactic fermentation is a secondary process that softens the wine's acidity but is not specifically related to the production of bubbles. Oxidative fermentation does not relate to sparkling wine and instead refers to a process that occurs in still wine production where exposure to oxygen changes the wine's characteristics. Therefore, secondary fermentation is the correct term that specifically refers to the fermentation process that happens post-bottling in the creation of sparkling wines.