Wine lovers will commonly come across the term ‘carbonic maceration’ once they become familiar with Beaujolais style wine made from Gamay grapes.

Carbonic maceration is a winemaking process in which whole grapes are placed in a sealed container and allowed to ferment in the absence of oxygen. This process is commonly used in the production of Beaujolais wines and is responsible for the unique fruity, floral aromas and flavors that are characteristic of these wines.

During carbonic maceration, the grapes are not crushed or destemmed, but instead are placed whole into a container, typically a large vat. The weight of the grapes on top causes the grapes at the bottom to burst, releasing juice that begins to ferment naturally due to the yeast present on the grape skins. As fermentation begins, the carbon dioxide produced by the yeast causes the remaining grapes to undergo an intracellular fermentation. This process creates a high level of carbon dioxide within the sealed container, which further encourages fermentation and prevents oxidation.

The resulting wine is typically light in color with a low tannin content and high acidity, making it fruity and easy to drink. Carbonic maceration is a relatively quick fermentation process, often lasting just a few days, and is favored by many winemakers as it can produce wines with unique flavor profiles in a relatively short period of time.

While carbonic maceration is most commonly associated with Beaujolais wines, it is also used in the production of other wines, such as certain Rioja wines from Spain and some Pinot Noir wines from Oregon. However, the process is not suitable for all grape varieties, as it can result in overly fruity wines that lack structure and complexity if used inappropriately.