Bordeaux wine almost universally used. Chaptalization is permitted, and is fairly common-place. Fermentation then takes place, usually in temperature controlled stainless steel vats. Next the must is pressed and transferred to barriques (in most cases) for a period of ageing (commonly a year). The traditional Bordeaux barrique is a 225 litre oak barrel. At some point between pressing and bottling the wine is blended. This is an integral part of the Bordeaux wine making process, as scarcely any Bordeaux wines are varietals; wine from different grape varieties is mixed together, depending on the vintage conditions, so as to produce a wine in
Bordeaux wine regions in fact exclusively lists red wine producers from the Haut-Médoc plus Château Haut-Brion of Graves, and (in a separate list) sweet white wine producers from Sauternes (including Barsac). Estates in the Médoc which were not classified in that listing may be classified under the Cru Bourgeois label. In 1953, a Classification of Graves wine was produced. Although this purports to classify the whole of Graves, it exclusively lists châteaux in Pessac-Léognan. In 1954, a separate classification of Saint-Émilion wine was set up for this Right Bank region. There are eight AOCs that cover the entire department of Gironde. Any producer