Worldwide, the production of vinegar is linked to that of alcoholic beverages. In France, the term "vinaigre" literally means vin aigre or "sour wine." In Japan, vinegar is made from fermented rice, just like sake. Also the lees of rice (sakekasu) pressed out of the sake after fermentation is completed, can be used for making vinegar. In both cases, acetic acid bacteria are added for a further fermentation process where ethanol is turned into acetic acid, which is the main component of vinegar. This takes one to two months after which the vinegar is filtered and pasteurized. Acidity is only just over 4% and the taste is mild. Rice vinegar also contains amino acids as well as citric acid, malic acid, lactic acid and succinic acid. Another type of rice vinegar with an even deeper taste is made from brown rice and popularly called kurozu, "black vinegar."
Rice vinegar is mixed with other ingredients to create condiments for specific purposes (the general name for these is awasezu, seasoned rice vinegar):
- sushizu, or sushi vinegar used to make vinegared rice for sushi, by adding sugar, salt and (sometimes) mirin;
- amazu, sweet vinegar, by adding sugar
- nihaizu, by mixing vinegar and soy sauce in the proportion of 3:2
- sanbaizu, by mixing vinegar, mirin (or sugar) and soy sauce in the proportion of 3:2:1