An onigiri is a hand-formed rice ball, salted on the outside, typically enclosing a moist filling and partially wrapped in nori. The shape (triangle, cylinder, flat round) and filling vary by region and season. The rice is plain or very lightly seasoned — the filling does the flavour work.
Classic fillings
- Umeboshi (pickled plum) — the original; tart, salty, antimicrobial
- Sake (grilled salted salmon) — the most popular in modern polls
- Tuna-mayo — a 1970s convenience-store invention that became canonical
- Kombu tsukudani — sweet-soy simmered kelp
- Mentaiko — spicy pollock roe
Shaping
Wet hands, palmed salt, rice at body temperature. Press firmly but not so hard the grains compact. The triangle shape holds its form; the cylinder is easier for beginners.