Rice vinegar is a mild, mellow vinegar fermented from rice or rice wine, clear to pale gold and far gentler than the sharp distilled and wine vinegars of the West. It is gently sweet, low in acidity and free of harshness, which makes it the everyday souring agent of East Asian cooking — the seasoning that turns plain steamed rice into sushi rice, and the backbone of dressings, dipping sauces, sunomono salads and quick pickles. Japanese, Chinese and Korean kitchens each keep their own styles, from water-clear komezu to inky Chinkiang black vinegar.