Fermented black beans are a little different to the beans I’m writing about on the rest of my website. While “black beans” usually refer to the Black Turtle Bean, originating from Mexico, sometimes the words are used to mean fermented black beans from Asia. These are actually made of soya, and are a different species of bean.
Fermented black beans are also called douchi (from Mandarin Chinese). They are a frequent ingredient in Cantonese Chinese cooking. (The Cantonese Chinese name for them is dul see). They also feature in Japan, Vietnam, the Philippines, and Cambodia.
They have a very intense flavour, similar to soy sauce but a bit deeper and more musky. Its flavour is comparable in intensity to garlic.
The beans are a source of umami flavour, just like soy sauce and miso. In case you didn’t know, umami is the fifth flavour to be identified as being sensed on the tongue (most other flavours are actually smells and are percieved via the inner nose). It is described as “savoury” or “meaty”. This umami quality of black beans make it a helpful flavouring for vegetarian and vegan recipes.
You can find fermented black beans in Asian supermarkets. They keep indefinitely, though you might want to put them in a sealed container to avoid them being eaten by moths.
Be careful when using black beans in your recipes! Apart from being very strong in flavour, they are also salty. So be sure to account for their salt when adding additional salt to a recipe. Some cooks call for them to be rinsed, which reduces both their saltiness and some of the intensity of their flavour.
Fermented black beans are delicious whole, mashed, or finely chopped. Try adding them to a sauce for tofu: just fry some finely chopped garlic and ginger, then add vegetable stock (Black Turtle Bean stock would work) or water and 1/2 a teaspoon of corn starch (a.k.a. corn flour – the light, powdery sort). Be sure to blend the corn starch with a little liquid before adding to prevent it from being lumpy. Add mashed fermented black beans and ring to the boil. If necessary, add a little more liquid or starch to create your desired consistency.
You can also buy premade black bean sauce. While not as fresh-tasting as homemade sauce, it has the value of being convenient. You can blend it into soups or stir-fries. Its rich flavour is quite versatile, and helps replace meat. Combine it with the meaty texture of firm tofu and an excellent synergy is formed.
Fermented black beans can also be soaked to make them softer and to allow them to blend better with recipes. Be sure not to throw away flavour with the soaking liquid, though; use it in your recipes. What also works is to just boil them for a short while; they become very soft and their flavour is diffused throughout the liquid.