Japan — Ibaraki Prefecture (Mito) and Kanto region claim particular cultural ownership; origin legend of Yoshiie Minamoto (11th century) leaving boiled soybeans in straw; modern commercial production from Meiji era
Natto (納豆) — fermented soybeans produced by Bacillus subtilis var. natto — is Japan's most polarising traditional food: beloved by most Japanese (particularly in the Kanto region) and deeply challenging to uninitiated visitors for its pungent ammonia-adjacent aroma, extreme stickiness, and mucilaginous threads. Despite being one of the world's most nutritious fermented foods (high vitamin K2, nattokinase enzyme, complete protein, probiotics), natto's sensory profile demands cultural acclimatisation. Production: soybeans are soaked, steamed, inoculated with B. natto starter, then incubated at 40°C for 18–24 hours. The resulting beans are covered in sticky, stringy biofilm and have developed the characteristic strong aroma. Commercial natto in Japan is sold in small polystyrene trays (3–4 per package) — Mito city in Ibaraki Prefecture claims Japan's natto capital status. Eating ritual: natto is typically mixed vigorously 50–100 times with the attached tare (soy-based sauce), karashi mustard, and spring onion before consumption — vigorous stirring increases the stickiness (activating the mucilaginous compounds further) and is considered non-negotiable by enthusiasts. Served over rice for breakfast or as a rice topper; incorporated into natto maki rolls, as a pizza topping in Japan, and in modern fusion applications.
Intensely savoury-ammonia, complex fermented depth, mucilaginous texture — an acquired taste; once acquired, irreplaceable
{"Vigorous stirring before eating: 50–100 stirs minimum — activates the sticky compounds; undisturbed natto is considered under-prepared","Mixing additions in order: tare sauce first (let it coat), then mustard, then spring onion — order affects final flavour integration","Temperature: natto served at room temperature has stronger aroma; refrigerator-cold moderates intensity for newcomers","Karashi (not wasabi): the provided mustard packet is specifically for natto — it cuts through the richness and suppresses excess ammonia notes","Quality tiers: small soybeans (kotsubu) are milder; large soybeans (okina natto) are stronger; organic premium brands have cleaner flavour","Introduction strategy: mix into hot rice immediately — heat and starch of rice absorb some of the intensity while preserving the probiotic benefit"}
{"Natto with avocado, wasabi soy sauce, and rice — a modern fusion that introduces natto to new eaters through familiar creamy richness","Natto miso soup: stir natto into dashi before adding miso — the combination of fermented bean and fermented soybean paste creates extreme umami depth","Homemade natto: steam soybeans, inoculate with store-bought natto as starter, incubate 24 hours — deeply satisfying process, dramatically better fresh","The ammonia note: perceived intensity decreases markedly after 10–15 tastings — acclimatisation is real; daily exposure builds appreciation"}
{"Not stirring — the uninitiated often avoid mixing; this produces an inferior eating experience with unintegrated flavour","Eating fresh from the cold fridge — room temperature (or slightly warmed) produces better flavour integration","Using too much tare sauce — the small packet is perfectly calibrated; excess tare makes natto aggressively salty"}
Sandor Katz, The Art of Fermentation; Elizabeth Andoh, Washoku