What Is Miso & How Do I Use It?

Miso soup, served alongside rice and pickles, forms the cornerstone of the traditional Japanese meal. But miso—the savory, fermented soybean paste now prized by chefs around the world—is more than just a quick and nutritious soup base. It's a fantastically versatile ingredient that will add a touch of umami magic to your culinary repertoire.

What is Miso?

Miso is made from boiled or steamed soybeans fermented with koji (grains, such as rice or barley, inoculated with the mold Aspergillus oryzae), salt and yeast. Koji, which breaks down starch molecules into sugar, is also a key ingredient in sake making and soy-sauce production. Traditionally, giant cedar casks were used for fermentation, which lasts from six months to several years. However, most commercial miso producers use stainless-steel tanks and shorten the fermentation period to a few months or even a few weeks. Longer fermentation leads to stronger, funkier flavors, while quicker fermentation typically yields miso with a mild, sweet-and-salty taste.

Origins and History of Miso

While the exact origin of Japanese miso-making remains unclear, the fermented food was introduced from China, most likely via Buddhist monks, during the 7th century. In the early days, miso was considered a luxury item, consumed exclusively in wealthy households and eaten either on its own or as a spread. Being so valuable, miso, like salt in Roman times, was sometimes used as currency to pay the salaries of government officials. As soybean production increased in the Muromachi period (1337 – 1573), farmers across the country began to make their own versions. During that time, the discovery that soybeans could be ground into a paste sparked new ways of cooking with the condiment. But, miso culture really flourished in the Edo era (1603 – 1868) with the proliferation of restaurants and miso shops.

Nutritional Value and Health Benefits of Miso

The Japanese saying, "Miso-wa isha irazu"—which translates as "If you eat miso regularly, you won't need to go to the doctor"—points to its reputation as a superfood. 1 tablespoon, or 17 grams, of miso provides 2.2 grams of protein and just under 1 gram of fiber. Plus, it contains important nutrients like vitamin K, which helps with blood and bone health, and zinc, which is good for both immuno- and metabolic health. The same amount also contains 634 milligrams of sodium, which is something to be aware of, especially if you follow a low- sodium diet for health reasons. Learn more about the health benefits of miso from a dietician.

As a fermented food, miso promotes the growth of healthy bacteria in the digestive tract. A diverse microbiome is thought to be linked to a number of positive health outcomes, ranging from better digestion to healthier cholesterol levels and lowered risk of some cancers. To get the maximum nutritional benefit, look for unpasteurized miso, and avoid cooking with it at high heat; temperatures above 158°F will kill the gut-friendly lactic bacteria and enzymes.

Types of Miso

While there are more than 1,000 varieties produced in Japan, miso is typically divided into categories by color:

White (beige to pale yellow) miso, which contains a higher proportion of grain, is fermented for a relatively short period of time, resulting in a smooth texture and pronounced sweetness.

Red (light brown to brown-black) miso contains a higher percentage of soybeans and undergoes longer fermentation, which gives the condiment an earthy, savory flavor. The darker the color, the saltier and more pungent the miso will be.

Awase (blended) miso is a mix of more than one kind of miso paste—a happy medium between the two styles. In general, lighter varieties work well in dressings and sweets, and darker pastes are suited to hearty stews and braises.

How to Use Miso

You can never go wrong with a comforting bowl of miso soup, but miso's savory richness can lend complexity to any style of cuisine. It can stand in for the flavor of Parmesan cheese in vegetarian and vegan dishes such as Vegan Spinach & Artichoke Dip, and add extra oomph to sauces, soups and stews. (Try this Chicken-Miso Curry.) Try it in dressings or as a dip for raw vegetables.

Miso makes a luscious glaze for Miso-Maple Salmon, and a sweet-and-salty marinade for flank steak (pro tip: use this as a filling for tacos). But it really shines with dairy, in a simple but elegant dish of Miso-Butter Turnips or spread onto a grilled cheese sandwich. Cream cheese marinated in white miso or a mixture of red miso and mirin is the ultimate snack to pair with sake. For a vegan version, try Miso-Marinated Tofu. And don't forget dessert: carrot cake with Miso-Cream Cheese Frosting puts a grown-up spin on a childhood favorite.

How to Store Miso

In theory, miso can keep indefinitely in the fridge, but it's usually at its best within about a year of purchase. It will continue to ferment and darken over time. As Japanese food expert and author Elizabeth Andoh told National Public Radio, spots of white or blue mold can be simply scraped off the surface, but if you notice any pink mold, discard the tub.

Bottom Line

Heathy and super-flavorful, miso is a foolproof way to up your cooking game. A little bit goes a long way, and the possibilities are endless. If you are salt-sensitive, you may want to limit your miso intake or consult your physician before incorporating miso into your eating routine. Otherwise, have fun with it and figure out which kind of miso you like best. Fermented foods add funk and depth to so many dishes, whether you're vegan, vegetarian, pescatarian or an omnivore, and it ups your daily intake of protein and fiber as well as that of key nutrients like vitamin K and zinc. People have been enjoying miso for more than a thousand years for a reason, don't miss out!