Riddling

The traditional method is the process used in the Champagne region of France to produce the sparkling wine known as Champagne. It is also the method used in various French regions to produce Crémant or other traditional method sparkling wines, in Spain to produce Cava and in Italy to produce Franciacorta. The method is known as the méthode champenoise, but the Champagne producers have successfully lobbied the European Union to restrict the use of that term within the EU to wines produced from their region. Thus, wines from elsewhere cannot use the term "méthode champenoise" on products sold in the EU, and instead the term "traditional method" (méthode traditionnelle) or the local language equivalent may be seen; for instance, in Germany the term used is "klassische Flaschengärung". South African wines from the Western Cape are labelled with the term "Methode Cap Classique". However, consumers outside the EU may see méthode champenoise used on labels for products made outside France.

Grapes are generally picked earlier, when sugar levels are lower and acid levels higher. Except for pink or rosé sparkling wines, the juice of harvested grapes is pressed off quickly, to keep the wine white.

The first fermentation begins in the same way as any wine, converting the natural sugar in the grapes into alcohol while the resultant carbon dioxide is allowed to escape. This produces the base wine. This wine is not very pleasant by itself, being too acidic. At this point the blend, known as the cuvée, is assembled, using wines from various vineyards, and, in the case of non-vintage wine, various years. After primary fermentation, blending (assemblage in Champagne) and bottling, a second alcoholic fermentation occurs in the bottle.

Although known as the Champagne method and associated with the name of Dom Pierre Pérignon in the late seventeenth century, the phenomenon of bottle fermentation was not unique to the Champagne region; it had already been used in Limoux, south western France since 1531 for the production of Blanquette de Limoux. Effervescence in wine was seen as a fault at the time and Perignon devoted much effort trying to eliminate it from the wines of Champagne. The process of secondary fermentation was first described by Christopher Merrett in a paper to the Royal Society, which included his observation that this could be encouraged by adding sugar to the wine before bottling. Concurrent improvements in glass manufacture in England also permitted the making of more robust wine bottles to contain the effervescence without exploding.

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Wikipedia