Bean paste is a broad term covering dozens of pastes made from beans that have been cooked, mashed, and often fermented or sweetened. The two major categories are sweet bean pastes, used in desserts and pastries across East Asia, and savory fermented bean pastes, used as flavor bases in soups, stir-fries, and marinades. What you’ll encounter depends entirely on which cuisine you’re exploring.
Sweet Bean Paste
The most widely known sweet bean paste is anko, a Japanese paste made from adzuki (red) beans cooked with sugar. It fills everything from mochi and dorayaki pancakes to taiyaki fish-shaped cakes. Anko comes in two main textures: tsubuan, where whole beans are boiled with sugar and left intact for a chunky consistency, and koshian, where the beans are pushed through a sieve to remove the skins and create a perfectly smooth filling. Koshian is the more common of the two.
White bean paste, called shiroan, is the other major Japanese variety. It uses pale-colored beans like butter beans, cannellini beans, navy beans, or a traditional Japanese variety called shirohana mame that grows in cooler regions like Hokkaido. White bean paste has a milder flavor than red, which makes it useful as a base that can be tinted with food coloring or flavored with ingredients like matcha or sweet potato.
In all sweet versions, the basic process is the same: soak the beans, boil them until soft, mash or strain them, and cook the mixture down with sugar until it reaches a thick, scoopable consistency. The result is dense, lightly sweet, and starchy, with a texture somewhere between jam and cookie dough.
Savory Fermented Bean Paste
Savory bean pastes get their depth from fermentation rather than sugar. These are essential ingredients in East Asian cooking, and each regional variety has a distinct character.
Miso (Japan) is made from soybeans combined with a grain like rice or barley and a starter culture called koji. Salt controls the fermentation. Some lighter varieties of miso are ready in as little as one week, while darker, more intensely flavored versions ferment for months or even years. Miso is the backbone of miso soup but also shows up in glazes, dressings, and marinades.
Doenjang (Korea) takes a simpler approach: just soybeans and salt, fermented in a sea salt brine for at least six weeks. The result is punchier and more assertively funky than most Japanese miso. It’s a core ingredient in Korean stews like doenjang-jjigae.
Doubanjiang (China) is a spicy, savory paste from Sichuan province made primarily from broad beans (fava beans) and chili peppers. It’s fermented and aged, sometimes for years, and provides the deep, complex heat in dishes like mapo tofu. The best-known versions come from Pixian county in Sichuan.
Tianmianjiang, or Chinese sweet bean sauce, sits somewhere between sweet and savory. It’s made from fermented soybeans and wheat flour, often blended with sesame paste and a touch of sugar. It has a smooth texture and a mild, rounded sweetness that makes it the traditional sauce for Peking duck and for wrapping with scallions in northern Chinese cooking.
Southeast Asian Varieties
When Chinese communities settled across Southeast Asia, they adapted soybean paste to local tastes. The result is tauco (also spelled taucu or taotjo), a yellow soybean paste found in Indonesia, Malaysia, Singapore, and Thailand. To make it, yellow soybeans are boiled, ground, mixed with flour, and fermented into a paste, then soaked in salt water and sun-dried for several weeks until the color shifts to a yellow-reddish tone.
Tauco originated from the mixing of Chinese and Sundanese food traditions in Cianjur, West Java, and today the major production centers in Indonesia are still in Cianjur and Pekalongan in Central Java. It’s used in stir-fries and braised dishes across Sundanese, Javanese, Malay, and Thai cooking. Vietnam has a similar fermented soybean paste called tương, which plays a comparable role in dipping sauces and cooked dishes.
Traditional vs. Commercial Production
The difference between traditional and factory-made fermented bean paste comes down to time. Historical records of soybean paste production in China go back over three thousand years. The traditional method involved exposing cooked soybeans to open air for at least three months so that naturally occurring microorganisms could colonize the material. That cultured mass was then mixed into a 20% salt solution, left to ferment for another one to two months, and finally aged for an additional two to three months. The whole process could take half a year or longer.
Commercial production compresses that timeline dramatically. A specific mold culture is added to a boiled soybean and wheat mixture and allowed to grow for just 24 to 48 hours under controlled conditions. The cultured material is then mixed with salt water and fermented at warm temperatures (around 104 to 113°F) for about one month. A final heating step sterilizes the paste and stops fermentation. The result is consistent and shelf-stable, though many cooks find that traditionally fermented pastes have more layered, complex flavor.
Nutrition and Fermentation Benefits
Sweet bean pastes are high in carbohydrates from both the beans and the added sugar, but they also retain fiber and plant protein from the whole beans. Smooth varieties that have had the skins removed lose some of that fiber.
Fermented bean pastes offer a different nutritional profile. The fermentation process generates bioactive compounds that aren’t present in the raw beans. Research on doenjang has found that Lactobacillus bacteria, which naturally colonize the paste during fermentation, convert glutamic acid into GABA, a compound involved in nervous system regulation. GABA levels in doenjang peak at around 179 days of fermentation. Bacillus strains found in fermented soybean products have also been linked to enzymes that support healthy blood circulation.
The main nutritional caution with fermented bean pastes is sodium. They’re salt-preserved by nature, so a single tablespoon can contain a significant portion of your daily sodium intake. A little goes a long way.
Storage
Sweet bean pastes, once opened, should be refrigerated and used within a week or two, as the sugar content makes them hospitable to mold. You can freeze sweet bean paste in portions for several months.
Fermented bean pastes are far more forgiving. An opened container of miso keeps for 6 to 12 months in the refrigerator, thanks to the salt and fermentation acting as natural preservatives. Doenjang and doubanjiang have similar staying power. Keep a clean spoon in the jar, store it sealed in the fridge, and the paste will hold its flavor for months. Over very long storage the color may darken and the flavor intensify, but it remains safe to eat.