Battera

An Osaka pressed-sushi (oshizushi) developed in the Meiji era (late 19th century), originally using gizzard shad (konoshiro), whose half-body pressed form resembled a small boat — 'bateira' in Portuguese, a word then in common use because Russian ships off Sakai were unloading via small craft — the loanword that gives the dish its name. When shad ran scarce, mackerel took over and stuck. It predates Edo nigiri in the region — Osaka-style pressed sushi was the older form.

Meiji-era Osaka pressed sushi named after the Portuguese 'bateira' (flat-bottomed barge), originally made with gizzard shad shaped like the boat. When shad ran scarce, mackerel took over. Predates Edo nigiri in the region.

A neat rectangle of vinegared rice topped with a thin slab of vinegar-cured mackerel and a translucent sheet of sweet-pickled kombu (shiro-ita kombu) over the top. Pressed firm in a wooden mold, sliced into squares. The fish is silver-skinned, pink underneath, soft but not raw-soft — the vinegar has tightened it. Eat with pickled ginger, no soy needed.

Curing is the load-bearing step — mackerel is salted heavily for 30–60 minutes (drawing out water and oxidation), rinsed, then bathed in rice vinegar 20–40 minutes depending on size. Under-cure and the fish reads slack and fishy; over-cure and the flesh goes opaque-white and rubbery. The kombu sheet on top isn't decoration — it cuts the oily mackerel with a sweet-sour wrap.