Horse mackerel (aji)
Located widely in warm sea waters throughout the world, horse mackerel are an adaptive migratory (wandering) fish species that ride warm currents. These fish can be classified into the species of horse mackerel, brownstriped mackerel scad, and striped jack mackerel. The horse mackerel is the most fished of the mackerel species, and it is sometimes classified according to size with those around 20 cm (7.9 in.) being called medium-sized horse mackerel and those under 10 cm (about 4 in.) being called small-sized horse mackerel (photo: horse mackerel).
Horse mackerel are available all year round, however the peak season for these fish is from June to August.
Contains protein and cholesterol-lowering polyunsaturated fatty acids (eicosapentaenoic acid, EPA). Horse mackerel extract contains high amounts of free amino acids including alanine, glycine and glutamic acid, and these extract components mix with lipids to create a characteristic umami flavor.
Connoisseur selection / storage
Horse mackerel with shiny eyes and bright metallic skin are fresh. Fish that are ungutted lose their freshness fast. Even when you do not plan to cook fish right away, gut and gill after purchase.
Fresh (sashimi-grade) horse mackerel can be used for tatataki (lightly seared, left raw in the middle), sashimi, and marinated dishes. These fish are also delicious grilled with salt, deep-fried, boiled, and as fishballs. Brownstriped mackerel scad are mostly used for dried fish products, and striped jack mackerel for sashimi, while small-sized mackerel often first deep-fried and then pickled in sweetened vinegar and/or ‘nanbanzuke’ (sweet and sour marinate).