太刀魚 · タチウオ · tachiuo
Tachiuo
Tachiuo is the largehead hairtail — a long, ribbon-shaped fish sheathed in brilliant silver, with soft, rich white flesh. The edible silver skin is the whole point.
- Also known as
- hairtail, cutlassfish, beltfish
- Species
- Trichiurus lepturus (Largehead hairtail / cutlassfish)
- Category
- Silver / shiny fish (hikarimono)
- Texture
- soft, melting — rich, mild, buttery
- Peak season
- Jul, Aug, Sep, Oct
- Sustainability
- varies — A wide-ranging, heavily fished species; the IUCN rates it Least Concern.
- Mercury
- Not in the FDA consumer table
- Pregnancy
- Eat in moderation
- Price tier
- $$$
A fish like a blade
Tachiuo means “longsword fish” (太刀魚), and one look explains it: a long, flattened, ribbon-shaped body sheathed in mirror-bright silver that gleams like a polished blade. That silver is a layer of guanine, it’s edible, and chefs leave it on — peeling it off would defeat the whole purpose.
Soft, rich, mild
The flesh is white, soft and surprisingly rich, almost buttery, with a clean and gentle flavor. It makes lovely nigiri, but it truly sings lightly torched (aburi), which crisps the silver skin and renders the fat. Summer into autumn is the season.
A global ribbon
The hairtail is among the most heavily caught fish on the planet — found in warm seas worldwide and rated Least Concern by the IUCN, which is also to say it’s fished hard everywhere. Its mirror finish makes it a natural match for spring’s sayori.
Related neta
Sayori
Sayori is the Japanese halfbeak — a slender, silver spring fish with a long needle-like lower jaw, prized for clean, lightly sweet, translucent flesh. Beautiful and delicate.
鰆 sawaraSawara
Sawara is Japanese Spanish mackerel — a large, pale-fleshed mackerel that's soft, mild and richest in winter, usually lightly seared or cured. Its kanji hides the word for spring.