Regional Cuisine Authority tier 2

Izu Islands Cuisine Shimoda Ashitaba and Shima-sushi

Izu Islands, Shizuoka — island chain extending south from Tokyo Bay; distinct island food culture

Overview

The Izu Islands — Izu Oshima, Niijima, Kozushima, Miyakejima, Hachijojima, and further islands — form a chain extending 300km south of Tokyo through the Pacific Ocean, politically part of Tokyo Metropolis but culinarily distinct through geographic isolation and subtropical climate. Island food culture: Oshima is known for anko (red bean), okowa (sticky rice with wild plants), and the camellia oil (tsubaki abura) tradition — the island's abundant camellia forests produce a cooking oil with neutral flavour and high smoke point that has been the cooking fat of choice for centuries. Hachijojima has the most distinct island culinary identity: shima-sushi (island sushi), which is sushi made with local fish marinated in soy and sugar rather than raw, reflecting the historical absence of refrigeration on remote islands — the fish is briefly cured and sweetened before placement on warm shari, producing a unique sweet-savoury profile quite different from Edo sushi. Ashitaba (Angelica keiskei) — a green leafy plant growing wild across the Izu Islands and Hachijojima especially — is the islands' most distinctive food product: deeply green, slightly bitter, extremely nutritious (chalcone compounds, vitamins), used fresh in tempura, stir-fried, in pasta, and dried as tea. The name means 'tomorrow's leaf' — cut one leaf today and tomorrow another sprouts in its place. Ashitaba tempura, ashitaba pasta, and ashitaba tea are island specialties that cannot be easily replicated with mainland ingredients.

Flavour Context

Izu Island food is flavoured by isolation — the ocean is the overwhelming presence: flying fish, silver herring, deep-sea fish at peak freshness; ashitaba adds a distinctive bitter-green mineral note; camellia oil imparts a subtle nuttiness; shima-sushi is sweet-savoury-tangy — island adaptations producing a unique flavour register not found on the mainland

Key Principles

{"Camellia oil (tsubaki abura) from Oshima: high smoke point, neutral to mildly sweet flavour — traditional island frying and cooking fat","Shima-sushi technique: local fish briefly marinated in sweet soy before sushi placement — island adaptation to pre-refrigeration conditions","Ashitaba freshness is critical — the bitterness and nutrient density diminish rapidly after harvest; island-sourced is superior","Island seafood isolation: surrounding waters provide unique species including kibinago (silver-stripe round herring), flying fish (tobiuo), and specific deep-sea fish not found on mainland menus","Hachijojima's distinct culture: the island had its own lord (daimyo) in the Edo period and developed independent food traditions","Island food as Tokyo omiyage: ashitaba products (tea, dried leaves, snacks) are the primary Izu Island souvenir"}

Pro Tips

{"Hachijojima requires a one-hour flight or overnight ferry from Tokyo — the food rewards justify the journey for serious food explorers","Oshima's camellia oil production: the harvest and pressing season in winter produces limited quantities of artisan cold-pressed oil","Flying fish (tobiuo) from Hachijojima: the seasonal arrival of flying fish schools around the island is an event — fresh tobiuo sashimi is extraordinary","Ashitaba tempura: the leaf's structure holds up beautifully in tempura batter; the bitterness is tamed by frying but the chlorophyll stays vivid","Kibinago silver herring: tiny, packed with omega-3s, traditionally eaten raw as kibinago no sashimi with a sharp sesame-vinegar sauce"}

Common Mistakes

{"Treating Izu Island cuisine as simply 'Tokyo food' — the geographic isolation created genuinely distinct traditions","Expecting conventional nigiri sushi at island restaurants — shima-sushi is the correct regional form","Substituting spinach or similar greens for ashitaba — the specific bitter chalcone compounds are not present in other greens","Cooking ashitaba at high heat for extended time — brief tempura frying or quick stir-fry preserves the green colour and nutrient density","Not exploring camellia oil as a cooking fat — its properties are genuinely different from standard vegetable oil"}

Source

Japanese Regional Cuisine Reference; Island Food Culture Documentation

Cross-Cuisine Parallels

{'cuisine': 'Greek', 'technique': 'Island food traditions (Crete, Santorini) — distinct from mainland cuisine through geographic isolation', 'connection': 'Both Greek islands and Japanese islands developed distinct food traditions through geographic isolation; capers and ashitaba both represent island-specific bitter greens with medicinal tradition'} {'cuisine': 'Hawaiian', 'technique': 'Indigenous island food culture — poi, fresh ocean fish, tropical plants as food', 'connection': 'Both Hawaiian and Izu Island food traditions developed in Pacific island isolation with abundant ocean access — fishing traditions and plant foraging as the food foundations'} {'cuisine': 'Canarian (Canary Islands)', 'technique': 'Gofio — island-specific flour; wrinkled potatoes with mojo — food developed through isolation', 'connection': 'Both traditions developed unique foods through island isolation; camellia oil parallels Canarian olive oil as island-specific cooking fat tradition'}