What is miso?
Miso, a.k.a. fermented soybean paste, is made by combining just three simple ingredients—soybeans, salt, and koji (a type of fungus cultivated on rice and other grains)—and allowing the mixture to age for months or even years. Factors like the type of koji used and the length of fermentation can result in infinite varieties of miso, including some that contain no soybeans at all (more on that below). In fact, over 1,300 variations of the umami-rich paste are in use today. It’s a vital ingredient in Japanese cooking, often used to bring a wallop of savory flavor to soups (like miso soup and hot pot), noodles, and yakitori dishes.
Types of miso:
In America, miso is often identified by its color, but labels of “red” or “white” do not even begin to cover the 1,300-plus types of miso found across Japan and the world. “Especially around Japan, you can go to miso stores, which are a bit like a deli,” notes Chung, “and buy each type of miso by weight.”
The two most popular types of commercially produced miso are shiro (white) miso and aka (red) miso. Though these varieties may look very different, they’re made from the exact same ingredients: soybeans, koji, and salt. “The difference is the fermentation time,” Chung notes. The longer miso ferments, the deeper in umami flavor and darker in color. But other factors play a role here, too, such as the type of grain used and the ratio of soybeans to koji (the higher the percentage of koji, the sweeter the miso will be).
Shiro (white) miso is a sweet, mild miso with a white or yellow color. It gains its light, delicate flavor from a high proportion of rice koji to soybeans and a short fermentation (three months to one year). Pair white miso with chicken, roasted vegetables, or a white fish like cod; you can also use it in marinades, salad dressing, or miso butter.
Aka (red) miso is a dark, rich miso made with a higher proportion of soybeans to rice koji. Aka miso ferments for a longer amount of time—typically six months to a year, but potentially up to five or 10 years—and ranges from reddish brown to nearly black in color. Its deep flavors can stand up to dark meat, hearty vegetables (use it in these mushroom burgers), oily fish like mackerel or salmon, and richer stews or braises like mabo don, a Japanese riff on mapo tofu.
In America, miso is often identified by its color, but labels of “red” or “white” do not even begin to cover the 1,300-plus types of miso found across Japan and the world. “Especially around Japan, you can go to miso stores, which are a bit like a deli,” notes Chung, “and buy each type of miso by weight.”
The two most popular types of commercially produced miso are shiro (white) miso and aka (red) miso. Though these varieties may look very different, they’re made from the exact same ingredients: soybeans, koji, and salt. “The difference is the fermentation time,” Chung notes. The longer miso ferments, the deeper in umami flavor and darker in color. But other factors play a role here, too, such as the type of grain used and the ratio of soybeans to koji (the higher the percentage of koji, the sweeter the miso will be).
Shiro (white) miso is a sweet, mild miso with a white or yellow color. It gains its light, delicate flavor from a high proportion of rice koji to soybeans and a short fermentation (three months to one year). Pair white miso with chicken, roasted vegetables, or a white fish like cod; you can also use it in marinades, salad dressing, or miso butter.
Aka (red) miso is a dark, rich miso made with a higher proportion of soybeans to rice koji. Aka miso ferments for a longer amount of time—typically six months to a year, but potentially up to five or 10 years—and ranges from reddish brown to nearly black in color. Its deep flavors can stand up to dark meat, hearty vegetables (use it in these mushroom burgers), oily fish like mackerel or salmon, and richer stews or braises like mabo don, a Japanese riff on mapo tofu.
As you dip into the container over time, oxidation will cause the miso to darken in color. To protect against oxidation, press a piece of parchment paper or plastic wrap onto the surface of the miso.
You can buy miso at most supermarkets, though Asian or Japanese specialty stores (or online Asian grocery purveyors) will likely have a wider selection. Here are a few of our favorite miso brands to shop online.
Shiro (white) miso
- Hikari Organic White Miso ($8 for an 18-oz. jar at Umamicart)
- Miko Brand Mutenka Koji Miso Paste ($7 for a 27-oz. jar at Weee!)
- Miso Tasty Organic Shiro White Miso ($14 for a 200-g jar at Amazon)
- Namikura Kyoto-Style White Miso ($13 for a 2.2-lb. bag at Milk Street)
Aka (red) miso
- Miso Master Red Miso Paste ($12 for a 16-oz. jar at Amazon)
- Miyasaka Red Miso ($10 for a 26-oz. jar at Umamicart)
- Miso Tasty Aka Red Miso ($23 for a 200-g jar at Amazon)
- Marukome Nama Koji Miso Paste ($8 for a 650-g jar at Weee!)
Artisanal US-made miso
Chung recommends seeking out miso made in Japan, given the country’s rich miso-making tradition, but you can also find quality miso from companies in the US that have been experimenting with various miso-making techniques. South River Miso—one of our favorite domestic miso companies—uses short-grain brown rice for its koji, whereas Maryland-based White Rose Miso uses Carolina Gold rice from nearby Marsh Hen Mill in its white miso.
These new-wave miso producers have also devised unique types of miso, some of which are soy-free. White Rose Miso offers benne miso and farro miso. Aedan Fermented Foods produces both traditional white miso, fermented for 12-plus months, and soy-free chickpea miso. South River Miso is the only known producer of adzuki bean miso, but it’s the three-year barley miso that stole our hearts (use it in this barley miso-marinated chicken yakitori).
