Cava is a Spanish sparkling wine made by the traditional champagne method. The wine undergoes a secondary fermentation directly in the bottle. Cava is traditionally made from three Catalan grape varieties: Xarel.lo - gives the sparkling wine its colour and strength, Macabeu - adds finesse, and Parellada - gives Cava its aroma. Other varieties are also used.
The process is as follows: a mixture of yeast, wine and sugar is added to the wine. The wine is sealed in a bottle which is stored in a cool cellar. This is followed by gradual fermentation for at least 9 months. The yeast converts the sugar into carbon dioxide. In addition to bubbles, lees are formed in the bottles. The bottle is turned daily to ensure that the lees reach the neck. After secondary fermentation, the neck is frozen and the sludge is removed. The bottle is then corked and secured with a wire lock to prevent the cork from being pushed out.