Acetic acid, or ethanoic acid, (CH3COOH) is a carboxylic acid. It is the main compound of vinegar, other than water.
It tastes and smells sour; it has no color. Its melting point is 16.5 °C(61.6 °F) and its boiling point is 118.1 °C(244.5 °F). It has a pH of 2.4.
Acetic acid is commonly used as a food additive. It has the E numbers E 260 (acetic acid).
Potassium acetate (E 261), sodium acetate (E 262), and calcium acetate (E 2639) are salts of acetic acid; they are commonly used to preserve food, usually vegetables. In sourdough, ethanol fermentation is used.