Sparkling wines: features and trends from tradition.

Sparkling wines contain at least three CO₂ pressure bars at 20°C. Carbonic gas is required to have an endogenous origin, obtained via a second fermentation, in the following European categories: sparkling wines and quality sparkling wines. In these types of sparkling wines, high gas pressure, together with other wine components, enables them to produce effervescence and foam when poured into the glass. The most commonly used grape varieties are Chardonnay and Pinot. Elaboration consists of two phases. In the first phase, the base wine is obtained after applying white vinification. The second phase consists of refermenting the wine, either in the bottle (champenoise or traditional method) or in isobaric tanks (Charmat method). The second fermentation requires the addition of "liqueur de tirage" to the base wine. The sparkling wines have a special biological aging or aging sur lies. As sparkling wines remain in contact with the lees, they develop sensory notes such as toasty, lactic, sweet, and yeasty, which can be attributed to proteolytic processes, components that would serve as the substrate for chemical and enzymatic reactions and to causes related with release-absorption between cell walls and the wine.