Mito Natto — Fermented Soybean Breakfast

Natto — fermented soybeans bound by sticky, stringy threads — is Japan's most divisive food, beloved by locals and bewildering to most foreigners. Mito is natto's spiritual capital. The city has been producing natto since the Edo period, and today over 30 natto manufacturers operate within city limits, from tiny family operations to industrial producers shipping nationwide.

The fermentation process involves inoculating steamed soybeans with Bacillus subtilis bacteria (natto-kin) and incubating them at 40°C for 20 hours. The bacteria produce enzymes that break down soy proteins into amino acids, creating intense umami, and synthesize poly-glutamic acid, which forms the characteristic sticky threads. Traditional Mito natto is wrapped in rice straw packets (wara-zuto), which naturally harbor natto bacteria and add subtle woody flavor. The proper way to eat it: stir 50 times to develop sticky threads, add mustard and soy sauce, stir again, then place over hot rice. The texture is slippery, the smell pungent, the taste savory-sweet-funky. It is not subtle, but it is nutritious and deeply traditional.