Black beans contribute to a flavoring most popular in the cuisine of China, where they are most widely used for making black bean sauce.
Douchi is made by fermenting and salting black soybeans. The black type soybean is most commonly used and the process turns the beans soft, and mostly dry (if the beans are allowed to dry). Regular white soybeans are also used, but this doesn't produce "salted black beans", instead these beans become brown. The flavor is sharp, pungent, and spicy in smell, with a taste that is salty and somewhat bitter and sweet