Fermented black beans, Douchi 「豆豉」or also known as Chinese fermented black beans is a unique seasoning widely used in Chinese cuisine to rich the depth of flavors. It is a fermented food made from soybeans, almost with yellow soybeans and sometimes black beans too. The "black" is actually describing the color presented after drying.

History of fermented black beans

Fermented black beans have a very long history in Chinese cuisine. There are records showing how to naturally make douchi in the Han dynasty. Ancient people found the way of fermentation by spores in the natural environment. The process of fermentation transforms soybeans into a fermented food that is rich in umami flavor. We seldom make fermented soy beans at home now. I only see my grandma make her version years ago because the city living room is not a good condition for fermentation.

With such a long history, fermented black beans have been finding different roles in several Chinese cuisines. Among those cuisines, Sichuan cuisine and Cantonese cuisine love to use douchi the most frequently.

In Sichuan cuisine, fermented black beans are most frequently used as an assistant seasoning of doubanjiang to create brilliant flavors like mapo flavor, and home-style flavor. The fermented black beans add a unique depth of flavor to these dishes that you can't find from any other ingredient. In Cantonese cuisine, fermented black beans are used in several classic steamed dishes like steamed ribs.

How douchi is produced

Douchi will go through two stages of fermentation. Soybeans are firstly soaked until soft and then steam until almost cooked. Then the beans are then naturally fermented by microbial or by the kit starter to import Aspergillus Oryzae. Yellow hair grows in the process. We wash the hair because it contains a bitter taste and then transfers the beans to a jar for months-long fermentation (this is the second fermentation stage). Along with the time, soy sauce and fermented beans are presented. This lovely stage is called watery douchi (水豆豉). The fermented beans are further dried (either by the sun or a dryer) in order to get a denser and more profound flavor. If you are interested in the process, check Doubanjiang. They share very similar processes.  The process of fermentation transforms soybeans into a seasoning food that is rich in umami flavor.

What do fermented black beans taste like

Since it goes through a long time of fermentation, douchi has a salty, pungent yet aromatic taste. It tastes a little bit salty when eaten raw but douchi should be used as condiments in dishes or mixed with other ingredients to make a sauce or paste.

Basic douchi contains only soybeans, mold or starter, and salt. But there are also brands that may use some spices like chili powder or five-spice powder. 

Are fermented soybeans healthy?

Like other fermentation food like natto, douchi contains lots of beneficial amino acids that can be good for our health. But it contains lots of sodium and thus spares the amount.

How to use fermented black beans

Douchi can be used directly in dishes. Lots of Sichuan dishes (mapo tofu, twice-cooked pork belly) call for douchi, not as the main seasoning, but it does improve the flavors and taste a lot.

Douchi can be used to make sauce or paste too. There are several famous sauce brands using douchi to make a lovely instant eating sauce like crispy chili with douchi from Lao Gan Ma. Douchi sauce from Lee Kum Kee.

Sometimes, douchi can also carry the main roles, in most cases with garlic to make yummy steamed dishes or douchi flavor stir fries including douchi steamed chicken. Check the following recipe ideas for more inspiration.

There is no need to rinse douchi before using if the amount is well controlled. But for those who need a special watch on sodium take-in, rinsing is optional.

Where to buy and How to keep

Most Asian store sells douchi or tries to get it from Amazon. Douchi is usually packaged in plastic bags, once opened, transfer them to an air-tight container and keep them in the fridge. Well-stored fermented black beans can be kept for six months.

Recipes using fermented black beans

Douchi, fermented black beans can be used to make ready-to-use sauces. Following is black bean and garlic sauce and another is spicy douchi sauce.

Fermented black beans can also be used in stews, soups, steamed dishes, and stir-frying. Following are some of the most popular dishes using douchi as the main seasoning.

In lots of Sichuan dishes, fermented black beans are also used as a side seasoning in addition to doubanjiang.

Hope you will love this magic ingredient. I and love to hear from you about your ideas of how to use black fermented beans and turn common ingredients into delicious ones.