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http://en.wikipedia.org/wiki/Vinegar#DistilledThe term "distilled vinegar" is something of a misnomer, because it is not produced by distillation but by fermentation of distilled alcohol. The fermentate is diluted to produce a colorless solution of 5% to 8% acetic acid in water, with a pH of about 2.4. This is variously known as distilled spirit, "virgin" vinegar,[7] or white vinegar, and is used in cooking, baking, meat preservation, and pickling, as well as medicinal, laboratory, and cleaning purposes.[8] The most common starting material in some regions, because of its low cost, is malt; in the United States, corn (maize), such as the Heinz brand.[9] It is sometimes derived from petroleum.[10]