After Fermentation

After fermentation, nearly all vinegars are pasteurized at 150–160°F/65–70°C to kill remaining bacteria of all kinds, but especially the aceto-bacteria themselves, which respond to the disappearance of the alcohol by metabolizing acetic acid to water and carbon dioxide and thus weakening the vinegar. Most vinegars are aged for a few months, a period in which their flavor becomes less harsh and more mellow, thanks in part to the combination of acetic and other acids with various compounds to form new, less pungent, often aromatic substances.