Back Appellation d'origine contrôlée, which applies to red, rosé and white wines produced throughout the Bordeaux wine-growing region, i.e. the entire Gironde department, with the exception of land unsuitable for vine cultivation. The diversity of soils, different exposures and variety of authorised grape varieties allow for the production of a wide range of wines. White wines are made from Sémillon, Sauvignon and Muscadelle grapes, with a maximum of 30% Merlot Blanc, Colombard, Ugni Blanc, Ondenc and Mauzac. AOC Bordeaux wines must contain at least four grams of residual sugar per litre. Those containing less are automatically classified as Bordeaux sec. Average production is 61,500 hectolitres. For red wines, the grape varieties used are Cabernet Sauvignon, Cabernet Franc, Merlot, Malbec, Carmenère and Petit Verdot, the latter two of which are in danger of extinction. These grape varieties can be used to produce light and refreshing Bordeaux rosés (approximately), Bordeaux clairets, wines with a paler red colour than rosés, obtained by maceration for several hours. Colourful but low in tannins, clairets are supple, very fruity and should be drunk within two years. Average production is 28,000 hectolitres. Bordeaux reds are very varied, ranging from supple wines to be drunk young to more tannic wines for ageing. Approximately 2,289,000 hectolitres are produced. There is also a Bordeaux Supérieur appellation, reserved for wines that meet specific conditions, notably a yield per hectare limited to 50 hectolitres per hectare. Production is 498,000 hectolitres of red and rosé wines and 2,400 hectolitres of white wines.