Natto (納豆)

Soybeans fermented with Bacillus subtilis (natto bacteria) into the sticky, stringy food eaten over rice.

What ferments it	Bacillus subtilis var. natto, cultured onto steamed soybeans; the sticky threads are polyglutamic acid produced during fermentation
Forms sold	Small foam or paper packs, usually three to a bundle, often with a small sauce and mustard sachet
Home ground	Strongest tradition in eastern and northern Japan; Mito, Ibaraki, is the famous natto town

Natto is Japan's most divisive fermented food: the smell (a mix that includes pyrazines shared with miso and roasted tea) and the threads that stretch from the beans divide even Japanese households. Its making is unlike any other page here - a single bacterial culture on whole beans, fermented warm for about a day, rather than a koji mash aged for months.

Eating notes, without ceremony: stir the pack well (the threads multiply), add the included sauce or plain shoyu, and serve over hot rice. Frozen natto is the export standard abroad and keeps its character well; thaw it in the refrigerator, not the microwave, for the best texture.

This page states composition facts only. Claims about natto and health are outside this guide's rules - see the About page for what we do not publish.

Natto (納豆)

See also