Even though—like miso and tempeh—it is made of fermented soybeans, sticky, earthy, funky natto does not receive the same love as its cousins. Slimy foods are just a little bit challenging to sell—no matter how high in protein or environmentally sustainable.
Let’s get the technicals out of the way: Natto is boiled soybeans that have been inoculated with Bacillus subtilis and left to ferment for about a day. The culture is found in a type of straw that was used historically in Japan to store food. Like yogurt, natto’s origin was likely accidental, probably involving an epicure discovering that she liked the taste of soybeans that had been wrapped in straw. Somewhere between the discovery that fermented soybeans are edible and 2020, natto became a Japanese staple.