Nigiri or pressed sushi made from horse mackerel (aji), a fish prized for its clean flavor but tricky handling — it deteriorates faster than other fish, so it must be marinated in salt and vinegar (shime) before being used for sushi. One of the most traditional edomae sushi toppings, predating the modern refrigeration era.
Aji sushi is an original edomae-zushi topping from the Edo period, when refrigeration did not exist and fish preservation relied on salt-vinegar curing (shime-saba and shime-aji techniques). The horse mackerel was abundant in Tokyo Bay and cured on the same day. Even with modern refrigeration, the shime process is retained because it tightens the flesh, balances the fish's oils, and adds tang. Aji remains a benchmark of a sushi chef's skill — the curing must be precise.
A piece of aji sushi presents a thin, slightly translucent strip of fish over warm shari. The fish is firmer than non-cured aji, with a clean, slightly tangy bite — the vinegar cure has brightened its oils. A dot of grated ginger and leek is often placed on top to balance the fish's natural oiliness. Eaten in one bite, with minimal soy.
Aji sushi's character depends on the shime (cure). The fish is salted heavily for 30-60 minutes to draw moisture and firm the flesh, then rinsed and soaked in rice vinegar for 20-40 minutes, which denatures surface proteins (turning the skin slightly translucent) and lowers the pH to slow bacterial growth. The cured fish is sliced thin and laid over shari (vinegared rice). The ginger and leek topping is not decorative — it enzymatically cuts the fish's oils.
Variations
Bo-zushi (pressed mackerel sushi) uses the same fish; some shops offer tataki-style seared aji.
On the Palate
Where Aji Sushi sits in the Japanese flavor cloud
Ingredients
Serves 2How it's made
6 steps · 20 min
- 15 min
Clean and fillet fresh aji; remove the small bones.
- 21 min
Salt the fillets heavily; rest 30-60 minutes.
Watch outSalt the fillets heavily and rest 30-60 minutes to draw moisture and firm the flesh — skimp here and the fish stays soft and watery.
- 31 min
Rinse and soak in rice vinegar for 20-40 minutes until the skin turns translucent.
Watch outSoak in rice vinegar just until the skin turns translucent — over-soak and the flesh goes chalky and sour instead of firm and bright.
- 43 min
Pat dry; slice thin pieces.
- 53 min
Form nigiri with vinegared shari rice.
- 61 min
Top each piece with grated ginger and chopped leek; serve immediately.
