White Miso Paste

Miso paste is prized for its ability to add complex, savory flavor to soups, dressings, sauces, and pickles. We also love it on broiled salmon and glazed chicken and have found that it can contribute incredible depth to nontraditional applications like braised potatoes and turkey burgers. An earlier iteration of miso (called jiang) originated in China some 2,500 years ago. In the seventh century, it was brought to Japan, where it became known as miso. Today, miso is an essential ingredient in Japanese, Chinese, and Korean cuisines. According to the Japan Miso Promotion Board, there are now 1,300 types of miso, several of which have become available to American shoppers since miso was first introduced to the United States in the 1960s.

In the test kitchen, we generally use two styles of miso: white (shiro) and red (aka). White is fairly sweet and mellow, while red tends to be more robust and salty. We call for white miso more often than red, so we decided to focus there first. Curious which products would deliver the best flavor, we purchased five widely available white miso pastes priced from $4.80 to $7.49 per package ($0.34 to $0.92 per ounce). Panelists sampled them in three blind tastings: plain, in miso soup, and in a marinade on broiled salmon. Throughout, we evaluated the flavor and overall appeal of each product.

How Is Miso Made?

As authors William Shurtleff and Akiko Aoyagi explain in The Book of Miso (1977), the first step in making miso is cultivating a mold called koji (Aspergillus oryzae), which is also a crucial component of soy sauce, sake, and fermented black bean paste. (It's not unlike the unique molds used to make blue cheese and Camembert.) Tiny spores of koji are typically sprinkled over cooked rice and spread across special trays in a carefully controlled environment. There, they incubate for two or three days as the rice ferments and the koji germinates.

Next, the koji is mixed with cooked soybeans, salt, and sometimes water. Here, different varieties of miso paste diverge; producers can adjust the ratio of koji to soybeans to alter the flavor profile. The mixture is left to ferment as the koji produces enzymes that break down the proteins, carbohydrates, and fats in the soybeans. One type of enzyme, called protease, converts the main protein in soybeans to amino acids, including glutamic acid, the source of miso's trademark umami flavor. At the same time, other enzymes break down the starches into simple sugars, which adds sweetness. Though some kinds of miso ferment and age for as long as two years, white miso is ready for packaging in just a few weeks or months.

Tasting Miso Paste

The miso ... read more