The initial step is the fermentation of wine by varieties of S.cerevaciae. This leads to the formation of ethanol which is a prolonged reaction. After completion of fermentation, the sediments settle down and the supernatant ethanol is partially oxidized by acetic acid bacteria, Acetobacter sps. in the presence of air. The optimum alcohol concentration is 10-13 percent.
Vinegar production is allowed to proceed till maximum strength is attained. The liquid is then stored anaerobically to prevent further degradation. Ageing takes place in storage. Esters are formed and the harsh flavor disappears. The vinegar is clarified by filtration, pasteurized and bottled.