Vinegar

Vinegar (from Old French vinaigre "sour wine") is a sour liquid made from the oxidation of ethanol in wine, cider, beer, or the like. Vinegar is typically 3-5% by volume acetic acid, and natural vinegars also contain smaller amounts of tartaric acid, citric acid, and others.

Vinegar may be started by the addition of mother of vinegar to wine or cider. The oxidation is carried out by acetic acid bacteria, as was shown in 1864 by Louis Pasteur.

It is commonly used in food preparations, particularly in vinaigrettes, and in the pickling process. It is also used as a condiment. For example, the British and Americans commonly use malt vinegar on fish and chips.

Malt vinegar is made by malting barley, causing the starch in the grain to turn to sugar. An ale is then brewed from the sugar and allowed to turn into vinegar, which is then aged. A cheaper alternative, called 'non-brewed condiment', is a solution of 4-8% acetic acid coloured with caramel.

White vinegar can be made by distilling malt vinegar, or may be nothing more than a solution of acetic acid in water.

Italian balsamic vinegar, made around Modena in Italy from white Trebbiano grape juice, is used in salad dressings. It is aged in wooden barrels to give it a dark color and sweet flavour.

The Japanese prefer a more delicate rice vinegar and use it for much the same purposes as Europeans.