Japan — the systematisation of sashimi knife cuts developed in parallel with the yanagiba knife during the Edo period as sashimi culture formalised in Edo and Osaka food traditions
The relationship between sashimi knife cut and eating texture is one of the most nuanced technical areas in Japanese raw fish preparation. Different species require different cuts because their muscle fibre orientation, fat content, and density vary significantly. The primary cuts are: (1) Hira-zukuri (flat cut) — the standard sashimi cut; 8–10mm thick slices drawn toward the body with a single pulling motion; appropriate for most firm white fish and tuna; (2) Usu-zukuri (thin cut) — translucently thin slices (2–3mm) for flounder, sea bream, and other delicate white fish where the paper-thinness creates a different textural register; (3) Kaku-zukuri (square cut) — thick cubes (15–20mm) for tuna, yellowtail, and other fatty fish where the larger surface area holds more wasabi-soy; (4) Ito-zukuri (thread cut) — extremely fine julienne for squid and other dense proteins where the thin strips create a different mouthfeel; (5) Tataki — a surface-seared preparation with visible flame markings; (6) Sogi-zukuri (angled cut) — the blade held at 45 degrees for broad, thin slices of salmon or other thick-fleshed fish. Each cut affects how the fish breaks apart in the mouth, how the wasabi and soy sauce interact with the flesh surface, and how the cooking finishes on the palate.
The cut is not itself a flavour — it is a texture-management decision that directly affects how flavour is perceived: thin cuts (usu-zukuri) allow quick, full flavour release; thick cuts (kaku-zukuri) hold flavour longer in the mouth; all cuts preserve the fish's natural flavour through non-thermal preparation
{"All sashimi cuts use a single pulling motion — never sawing; the pulled cut severs muscle fibres cleanly without compression","Usu-zukuri requires the thinnest, sharpest possible blade — a yanagiba at maximum sharpness; any blade drag tears the translucent slice","Cut direction relative to muscle grain matters: cutting across the grain shortens the fibres (more tender); cutting with the grain lengthens them (chewier)","Hira-zukuri thickness (8–10mm) is calibrated for the wasabi-to-fish ratio in a single bite — thinner produces too little fish; thicker dilutes the seasoning","Plating direction: fan slices toward the guest, not away — this is the ritual presentation direction, not merely aesthetic"}
{"Chilling the cutting board: a cold cutting board prevents the fish surface from warming during extended cutting — essential for long cutting sessions","Hira-zukuri rhythm: aim for 5 slices in 5 seconds for medium-sized fish preparations — too slow allows the flesh to warm","Usu-zukuri demonstration value: the translucent slices fanned in a circle communicate the chef's knife skill instantly — a signature of the sashimi course's opening presentation","Kaku-zukuri of toro: large cubes of otoro (fatty tuna belly) allow the fat to coat the entire surface of the mouth — the cube format maximises the fat perception"}
{"Sawing through fish with a sashimi knife — this is functionally impossible with a properly sharp yanagiba; if you are sawing, the knife needs sharpening","Cutting against the muscle grain for all fish — some fish (bonito, tuna) are better cut slightly with or across the grain depending on desired texture","Usu-zukuri from thick fish without adjusting the knife angle — for wide fish, the angle change is needed for consistent thin slices","Cutting sashimi at room temperature — sashimi should be cut from properly chilled fish; warm fish does not hold its cut edges cleanly"}
Japanese Cooking: A Simple Art (Shizuo Tsuji) / Nobu: The Cookbook (Matsuhisa)