The Spanish Mackerel is available year round, but it is especially good during the summer. The fat content is highest during this period since it gets ready to mate.
It has a unique scale (zeigo) that looks like a zipper, and runs along the length of its body.
The word aji is phonetically identical to the word “taste” in Japanese, and is believed to bare its name for a good taste, and was a popular fish for the lower class for its affordable price.
Sometimes it is said to taster better than the Red Snapper, which is considered the “King of Fishes” in Japan.
Fresh Spanish mackerel was most likely not available at most times during the Edo period, and was enjoyed as a tataki or a sashimi that is flavored with condiments.
The Spanish mackerel version of tataki consists of sliced scallions, perilla, myoga, garlic, and miso paste. These ingredients along with are roughly chopped and served on a small plate.
While this made it harder for the actual flavors of the Spanish mackerel to be tasted, it was the only option when it wasn’t extra fresh and needed extra condiments to the refine the taste.