Douchi

Douchi (Chinese: 豆豉; pinyin: dòuchǐ), also known as doushi, shi, or tochi, is a group of fermentation-processed soybean foods most popular in the cuisine of China. The most common type of douchi, made from salted black soybeans and typically called fermented black soybeans (Chinese: 黑豆豆豉; pinyin: hēidòu dòuchǐ), Chinese fermented black beans, or salted black beans, is most widely used for making black bean sauce dishes. Douchi is made by natural fermentation of soybeans. Douchi can be classified as mold-fermented douchi (Aspergillus-type, Mucor-type, or Rhizopus-type) or bacteria-fermented douchi (typically Bacillus-type). There are two main stages to the typical douchi-making process: first cooked black soybeans undergo natural mold growth and fermentation, then they are salted to continue fermentation. A maturation stage may follow, in which the douchi is aged in brine or with other ingredients to develop flavor. The process turns the beans soft, and if allowed, semi-dry. When regular (yellow) soybeans are used, the process does not produce "salted black beans"; instead, the beans become brown. The smell is sharp, pungent, and spicy; the taste is salty, somewhat bitter and sweet. Products made with yellow soybeans include shuidouchi (bacteria-fermented) and mianchi (mold-fermented). Chinese fermented black beans are not the same as the black turtle bean, a variety of common bean that is commonly used in the cuisines of Central America, South America, and the Caribbean.