Natto
Traditional Japanese fermented soybean food with a strong flavor.
Natto is a traditional Japanese food made from whole soybeans fermented with Bacillus subtilis var. natto. It is often served as a breakfast food with rice, accompanied by karashi mustard, soy or tare sauce, and sometimes Japanese bunching onion. Within Japan, natto is most popular in the eastern regions, including Kantō, Tōhoku, and Hokkaido.
- type
- Fermented soybean food
- origin
- Japan
- main ingredient
- Soybeans, Bacillus subtilis var. natto
- key flavor
- Strong, pungent, umami
- texture
- Sticky, slimy
- popular regions
- Kantō, Tōhoku, Hokkaido
Lore & Background
Sources differ about the earliest origin of natto. One theory is that natto was codeveloped in multiple locations in the distant past, since it is simple to make with ingredients and tools commonly available in Japan since ancient times. One legendary origin attributes natto to the samurai Minamoto no Yoshiie (1039–1106), who was on a campaign in northeastern Japan between 1086 and 1088 AD. His troops boiled soybeans for their horses, but were attacked and hurriedly packed the beans in straw bags. Days later, the beans had fermented; the soldiers ate them and liked the taste, and Yoshiie also liked it. Another story involves leftover boiled soybeans wrapped in straw, which fermented and were found delicious—though this legend is often misattributed to Prince Shotoku (574–622), the tale actually dates from a later period and is not directly connected to him.
Reader's Guide
Natto is often considered an acquired taste because of its powerful smell, strong flavor, and sticky, slimy texture. A 2009 survey revealed that 70% of 3,827 respondents found the taste pleasant, while others eat it out of habit. The dish is eaten cold with rice, often mixed with soy sauce or karashi mustard. It is also used in natto sushi, natto toast, miso soup, tamagoyaki, salad, okonomiyaki, chahan, or spaghetti. For those who dislike the smell and texture, dried natto and fried natto were developed around 1990, and a less sticky variety called mamenoka has also been created. Natto is more popular in eastern Japan (Kantō, Tōhoku, Hokkaido) than in Kansai. Its odor comes from diacetyl and pyrazines; over-fermentation releases ammonia. The fermentation develops glutamic acid, giving it umami flavor. Similar fermented soybean foods exist across Asia, including shuidouchi in China, cheonggukjang in Korea, thua nao in Thailand, and kinema in Nepal and parts of India.
Did You Know?
- Natto is made by fermenting soybeans with Bacillus subtilis var. natto at 40°C for up to 24 hours.
- A 2009 survey found that 70% of 3,827 respondents found natto's taste pleasant.
- Natto is a rich source of iron (15% DV), manganese (38% DV), and vitamin K (361% DV) per 50-gram serving.
- The Chinese character 豉 (chǐ) for fermented soybeans is not historically attested with the pronunciation 'kuki' in reliable sources, and its entry into Japan is not clearly documented in the 8th century.
Frequently Asked Questions
Who is Natto?
Natto is a traditional Japanese dish made from whole soybeans that have been fermented using the bacterium Bacillus subtilis var. natto. It is best known as a staple breakfast item served over hot rice.
What are Natto's powers/role?
Natto is defined by its intensely sticky, stringy texture and a bold, pungent umami flavor that sets it apart from other soybean preparations. It typically appears on the plate alongside karashi mustard, soy or tare sauce, and sliced green onion.
How does Natto's story end?
In most households, natto's arc concludes at the breakfast table, where it is mixed thoroughly with rice and its accompaniments before being eaten. It is a single-bowl, one-sitting experience rather than a multi-course affair.
Why is Natto important?
Natto holds a deeply rooted place in Japanese food culture, particularly as a morning ritual in the eastern regions of Kantō, Tōhoku, and Hokkaido. Its long history as an accessible, protein-rich fermented food has made it a cultural touchstone in those areas.
What is Natto's origin?
Natto traces its roots to Japan, where soybeans are inoculated with a specific strain of Bacillus subtilis and left to ferment, producing the characteristic slime and aroma. The result is a whole-food, single-ingredient preparation that has been enjoyed for centuries.
More in Fermented Foods 1-17
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