Japan — Pacific and Sea of Japan coastal fisheries
Hirame (ヒラメ, bastard halibut, Paralichthys olivaceus) and karei (鰈, Japanese flounder/sole, various Pleuronectidae species) are both flatfish that are frequently confused outside Japan, though Japanese cooks make a precise distinction between them based on eye position: 'Hidari hirame no migi karei' (左平目の右鰈) — hirame's eyes are on the left side of the body when the fish is placed with the dorsal fin upward; karei's eyes are on the right. This simple mnemonic distinguishes the two groups across all species. Hirame is considered more prestigious for sashimi use — the white, firm flesh is among the most delicate in Japanese raw fish culture, with an exceptionally clean, sweet, and mild flavour. The engawa (縁側) — the narrow fin muscle that runs along the edge of the fish body — is particularly valued: the constant movement of the fin develops this muscle into a firmer, richer, more intensely flavoured cut that is priced higher than the main body flesh in sushi bars. Karei (which includes a wide range of flounder species) is generally considered less premium but is excellent simmered (karei no nitsuke — braised flounder in soy and mirin). Both fish are winter-season premium products. The skin of both species is also served: karashime (lightly salted and acid-treated skin) is a delicacy at high-end sashimi restaurants.
Hirame sashimi: exceptionally clean, mild, slightly sweet with a firm yet yielding texture. One of Japan's most 'pure' flavour experiences — the fish is almost transparent in both colour and taste, the quality entirely in the freshness and cut. Engawa: richer, firmer, with a more pronounced oceanic character. Karei nitsuke: the firm flesh takes on sweet-savoury broth character while maintaining structural integrity — a deeply satisfying simmered dish.
{"The eye-position rule (left=hirame, right=karei) applies across all flatfish species without exception","Hirame for sashimi should be cut against the muscle grain — thin, delicate slices that showcase the translucent white flesh","Engawa requires different cutting — the dense, fibrous fin muscle should be thinly sliced on an extreme bias to shorten the fibres","Karei no nitsuke: the fish must be cleaned with the skin scored (2–3 diagonal cuts) before braising to prevent the skin contracting and curling during cooking","Both fish should be served with grated daikon and soy — the daikon's mild enzyme activity complements the delicate protein structure"}
{"Premium hirame sashimi is served in the Edomae tradition with a touch of sudachi juice rather than lemon — the citrus character of sudachi enhances the delicate sweetness","Hirame kobujime (kelp curing) is the definitive preparation: 2 hours in dampened Rishiri kombu produces a firmer, more umami-rich sashimi that is considered superior by most traditional chefs","Karei no nitsuke broth (soy, mirin, sake, ginger) is drunk as a final course in traditional Japanese meals — the fish's collagen has dissolved into the broth","The liver of both hirame and karei (found in winter fish) is considered a delicacy in coastal fishing communities — briefly grilled with salt","Sōgizukuri (diagonal-pull cut) is the classic hirame sashimi cut — the long pulling motion produces slices with greater surface area that dissolve more readily on the tongue","Karei is less expensive than hirame and makes a better everyday fish — nitsuke with root vegetables and ginger is one of Japan's most satisfying winter home-cooking preparations"}
{"Misidentifying hirame as karei — the distinction matters for pricing, preparation method, and seasonal appropriateness","Not scoring karei skin before braising — the skin contracts and lifts, producing an uneven, visually poor result","Neglecting the engawa — this is the most flavourful part of hirame and should always be offered in sashimi service"}
Tsuji: Japanese Cooking — A Simple Art