By Yoshi | Japan Unveiled
On the specific midsummer day known as Doyo no Ushi no Hi (土用の丑の日 — the Day of the Ox in the Doyo period, which falls in late July), something specific happens to Japanese supermarkets, department stores, and delivery services that has been happening every year since approximately the eighteenth century: the entire country appears to decide, simultaneously, to eat eel.
The queues outside dedicated unagi (鰻 — eel) restaurants begin before opening. The supermarket refrigerator sections, usually reliable in their specific eel-adjacent supply, run out of the specific kabayaki-glazed eel fillets that the specific holiday requires by early afternoon. The convenience stores, which have pre-stocked specific quantities that their specific sales data predicted would be adequate, discover that their specific predictions were not adequate. Japan consumes approximately sixty percent of its annual eel supply in the specific weeks surrounding this specific day.
The specific reason for this specific synchronised national appetite: tradition, marketing, and a specific eighteenth-century food scholar’s specific recommendation — a specific combination that has sustained one of Japan’s most beloved food rituals for approximately two and a half centuries, and that continues to drive the specific most intense single-day food purchasing event in the Japanese food calendar.
This article is about unagi — the specific eel that Japan loves with a specific intensity unmatched by any other national food culture — its specific preparation, its specific cultural history, and the specific contemporary challenges that the specific declining wild eel population and the specific difficult aquaculture situation present to the continuation of this specific beloved tradition.
The Specific Eel: What Japan Eats
Japan primarily consumes the specific Japanese eel (Anguilla japonica — 日本鰻, nihon unagi), one of four Anguilla species found in East Asia, a specific catadromous fish (one that lives in fresh water and migrates to the sea to spawn) whose specific life cycle remains one of the most mysterious in all of ichthyology. The specific spawning ground of the Japanese eel — identified only in 2009, through specific oceanographic tracking research, as the specific seamount area near the Mariana Islands in the specific western Pacific — was unknown to science until that specific year, meaning that Japan had been eating and culturally celebrating a fish whose specific fundamental biology it did not understand for the entire approximately two thousand years of the specific eel eating tradition.
The specific eel’s flavour: rich, sweet, slightly gelatinous from the specific subcutaneous fat layer, with a specific depth that comes from the specific combination of the specific wild fish’s specific diet and the specific kabayaki preparation that is the specific primary cooking method. The specific fat content of the Japanese eel — higher than most freshwater fish, concentrated in specific layers beneath the specific skin — is the specific source of the specific richness that makes eel the specific quintessential Japanese summer stamina food. The specific traditional understanding: eating the specific fatty eel in the specific hot summer replenishes the specific energy depleted by the specific heat, a specific traditional medicine logic that the specific contemporary nutritional understanding of the specific eel’s specific vitamin B1, specific DHA, and specific EPA content partially validates.
Kabayaki: The Specific Preparation
Kabayaki (蒲焼き — reed-fire grilling) is the specific preparation method that defines Japanese eel cooking and that distinguishes the specific Japanese approach from every other eel-cooking tradition in the world. The specific kabayaki process:
The specific live eel is killed with a specific knife thrust to the head and then split open — in the specific Kanto (Tokyo) style, split from the back (sebiraki — 背開き) and the head removed; in the specific Kansai (Osaka) style, split from the belly (harabiraki — 腹開き) with the head left attached. This specific difference between the two regional styles reflects a specific historical cultural difference: the specific Edo samurai culture’s specific reluctance to use the specific belly-split method that suggested cutting open in a manner associated with the specific suicide ritual of seppuku. The specific Kansai merchant culture, less burdened by the specific samurai aesthetic conventions, maintained the specific original belly-split technique.
After splitting, the specific eel is skewered and grilled briefly over specific charcoal — the specific initial grilling that firms the specific flesh. The specific Kanto-style preparation then steams the specific eel (the specific mushiyaki — 蒸し焼き step that produces the specific extremely soft, specific fluffy texture of the Kanto style), then grills again with specific repeated applications of the specific sweet soy sauce glaze (tare) until the specific layered caramelised surface of perfect kabayaki is achieved. The specific Kansai style skips the steaming and grills entirely from start to finish, producing a specific firmer, more directly flavoured result that the specific Kansai palate prefers.
The specific kabayaki tare: the specific sweet soy sauce glaze that defines kabayaki is produced from a specific base of soy sauce, mirin, and sake reduced to a specific consistency, with specific sugar added, and then maintained in a specific continuous preparation — the specific eel restaurant’s specific tare that has been in continuous use for decades, refreshed with specific additions but never fully replaced, accumulating the specific specific depth of the specific specific years of use. The specific tare at a specific long-established Tokyo unagi restaurant is literally a product of decades of accumulated eel cooking — the specific caramelised proteins and the specific specific Maillard products of hundreds of thousands of eel preparations are present in the specific tare, and their specific contribution to its specific character is genuine and irreplaceable.
Unadon and Unaju: The Rice Delivery Formats
Unadon (鰻丼 — eel rice bowl) and unajū (鰻重 — eel lacquer box) are the specific standard serving formats for kabayaki eel in the Japanese restaurant context — the specific preparations in which the specific hot kabayaki-glazed eel is placed on or over specific hot steamed rice in either a specific ceramic bowl (unadon) or a specific lacquer box with a fitted lid (unaju).
The specific lacquer box distinction: the specific unaju presentation — in the specific traditional lacquer box whose specific lid traps the specific steam from the specific hot rice and the specific kabayaki, allowing the specific combined aromas to develop before the specific lid is lifted — is considered the more formal and the more specifically aesthetic of the two formats. The specific moment of lifting the specific unaju lid — the specific specific release of the specific combined aroma of the specific kabayaki tare and the specific hot rice — is one of the most specifically anticipated specific sensory moments in the specific Japanese formal meal experience.
Hitsumabushi: Nagoya’s Specific Contribution
Hitsumabushi (ひつまぶし) — the specific Nagoya preparation of kabayaki eel that is arguably the most specifically interesting of all Japanese eel preparations — is a dish I have eaten many times in the specific restaurants of Nagoya and that I consider one of the specific clearest examples of the specific Japanese culinary intelligence that produces the specific maximum possible pleasure from a specific ingredient by changing the specific context of its presentation and consumption.
The specific preparation: kabayaki eel is served in a specific round wooden rice tub (ohitsu — お櫃), mixed with the specific hot rice and the specific specific tare glaze, with specific additional condiments served alongside — the specific specific nori (dried seaweed), the specific specific green onion, the specific specific wasabi, and the specific specific dashi broth for the specific final eating stage.
The specific three-stage eating experience that hitsumabushi prescribes:
The specific first portion: the specific first quarter of the ohitsu, eaten as-is — the specific pure flavour of the specific kabayaki eel and the specific hot rice with the specific tare, without additional condiments. The specific first encounter with the specific unadulterated flavour.
The specific second portion: the specific second quarter, eaten with the specific condiments — the specific nori, the specific green onion, and the specific wasabi added, changing the specific flavour profile toward the specific sharper, more complex character that the specific condiment additions produce.
The specific third portion: the specific third quarter, eaten as ochazuke (お茶漬け) — the specific hot dashi broth poured over the specific eel-and-rice combination, producing the specific specifically different preparation in which the specific broth’s specific clean umami depth transforms the specific kabayaki from a specific rich, direct preparation into a specific lighter, more specific broth-forward experience. The specific fourth portion is eaten in whichever of the three specific ways the specific diner found most satisfying.
This specific three-in-one structure — the specific same ingredients experienced in three specific fundamentally different ways within the specific same meal — is the specific expression of the specific Japanese food philosophy of maximising pleasure through specific contextual variation that I find most compelling and most specifically Japanese.
The Conservation Crisis: The Disappearing Eel
The specific Japanese eel (Anguilla japonica) was listed as an endangered species on the IUCN Red List in 2014, and the specific population has declined by approximately ninety percent since the 1960s — a specific decline whose specific causes are multiple and specific: specific overfishing of the specific wild eel supply (both the specific adult eel and the specific specific juvenile eel, the specific shirasu unagi — glass eel — that is the specific foundation of the specific eel aquaculture industry), specific habitat loss from the specific specific river management practices that have altered the specific freshwater environments the specific eel requires, and the specific specific disruption of the specific oceanic migration that the specific specific climate changes have produced.
The specific aquaculture situation: almost all commercially sold Japanese eel (approximately ninety-nine percent) is farmed rather than wild-caught — but the specific Japanese eel aquaculture is not a closed cycle. The specific eel cannot be commercially bred in captivity; the specific glass eels that the specific aquaculture industry requires must be caught from the specific wild populations as specific juveniles. The specific wild glass eel catch — on which the specific entire farmed eel supply depends — has declined dramatically, driving the specific specific wild glass eel price to extraordinary levels (specific years have seen specific prices exceeding 1,000,000 yen per kilogram for specific wild glass eel) and directly driving the specific retail kabayaki price that has made eel an increasingly expensive and increasingly occasional food rather than the specific accessible everyday preparation it once was.
The specific Doyo no Ushi no Hi tradition that I described at the beginning of this article — the specific annual national eel-eating day — is itself part of the specific problem: the specific concentrated single-day demand that the specific holiday creates produces the specific specific purchasing pressure that the specific specific supply chain cannot sustainably meet. The specific contemporary Japanese conversation about eel combines the specific pleasure of the specific tradition with the specific specific anxiety of the specific specific sustainability challenge in a way that reflects the specific specific honest difficulty of maintaining specific specific beloved food traditions in the specific specific face of specific specific ecological reality.
— Yoshi 🐍 Central Japan, 2026
Enjoyed this? You might also like: “Nagoya Meshi: The Bold Flavours of Central Japan” and “Japanese Seafood Beyond Sushi: What the Ocean Offers” — both available on Japan Unveiled.
