We are still learning about how Sparkling wines are made.
The base wine grapes are picked a bit younger to preserve acidity and fermented into a dry wine.
The winemaker then takes the various base wines and blends them together into what the French call a ‘cuvée’, which is the final sparkling wine blend.
Tirage yeast and sugars are added to the cuvée to start the second fermentation and the wines are bottled and topped with crown caps.
The second fermentation takes place inside the bottle, which adds about 1.3% more alcohol and the process creates CO2 which is trapped inside the bottle thus carbonating the wine.
The yeast dies in a process called autolysis and remain in the bottle. For the aging,
Sparkling wines are aged on their lees (the autolytic yeast particles) for a period of time to develop texture in the wine.
Champagne requires a minimum of 15 months of aging (36 months for vintage Champagne).
The Cava requires a minimum of 9 months of aging but requires up to 30 months for Gran Reserva Cava. Most believe the longer the wine ages on its lees, the better.
Riddling clarification occurs by settling the bottle upside down and the dead yeast cells collect in the neck of the bottle while the disgorging removes sediment from bottle.
The bottles are placed upside down into freezing liquid which causes the yeast bits to freeze in the neck of the bottle.
The crown cap is then popped off momentarily which allows the frozen chunk of lees to shoot out of the pressurized bottle.