Japan Tourism / Boso Peninsula in Chiba Prefecture Offering Experience of Fresh ‘Gold’ Horse Mackerel and ‘Prime’ Mackerel

Kei Aotani / Ryoko Yomiuri Publication
Tokyo Wan Ferry, which sails between Kanaya Minato and Tokyo Bay in 40 minutes

Horse mackerel (aji in Japanese), mackerel (saba), sardine (iwashi), and other so-called “blue-skinned fish” can go bad quickly, so freshness is essential. Although freezing technology to help keep their freshness has remarkably progressed, it is still best to visit places near fishing ports and eat ocean-fresh fish there.

To experience tasty blue-skinned fish, I traveled to the Boso Peninsula in Chiba Prefecture. The peninsula is surrounded by the calm waters of Tokyo Bay inside and the rough waters of the Pacific Ocean outside. The inside area is called Uchibo and the outside area Sotobo. This geographic feature ensures to land a wide variety of seafood.

First, I went to Kanaya Port in Futtsu in the Uchibo area. The port is a terminal of the Tokyo Wan Ferry, which crosses Tokyo Bay to reach Kurihama Port in Kanagawa Prefecture. To the east of the port is Mt. Nokogiri featuring a distinctive jagged ridge. Near the port, I saw a banner that reads Kogane-aji Furai (deep-fried gold horse mackerel) in front of the Kanaya Shokudo restaurant, which I entered.

Kogane-aji is a Japanese species of horse mackerel. Kogane-aji uniquely inhabits shallow waters without migrating to the open sea and has a yellowish body, which explains why its name includes the term “kogane” (gold).

“Shallow waters where kogane-aji inhabit are rich in food for the fish, so they have more fat and plump bodies than the same species from the open sea,” said Munenobu Nagata, the restaurant manager.

Nagata also said: “Our restaurant’s deep-fried gold horse mackerel is trademarked. To serve the dish, we use Japanese horse mackerels that I individually determine as ‘kogane-aji’ among those caught mainly near the Boso Peninsula.”

Seeing the fried fish, I was surprised at its size. On the day, the whole length of fillets longer than 15 centimeters each were being deep-fried. When it was served to me, I immediately had a bite and was surprised again. Savory fish meat juice was flowing from the soft meat, just like a hamburger steak.

Kei Aotani / Ryoko Yomiuri Publication
A ¥1,848 set meal from Kanaya Shokudo including fried “gold” horse mackerel and two other fried local fishes

It was a good start of my gourmet trip. I can expect more to come, I thought to myself.

Kei Aotani / Ryoko Yomiuri Publication
A fresh fish store next to Kanaya Shokudo sells sun-dried fish.

Prime mackerel safe to eat raw

After managing to resist various temptations in port towns on my way, including kinmedai alfonsino caught in the Sotobo area in Katsuura, clams in Kujukuri, and octopus in Isumi, I finally arrived at the Choshi Fishing Port, located in the eastern end of the peninsula.

The fishing port is huge, featuring three wholesale markets. Its annual catch had been the largest in Japan for 12 consecutive years until 2022.

Mackerel, the fish representing the port, is in season between October and February. Only one out of every 100 weigh 700 grams or more, which are called “gokujo saba” (prime mackerel) and are highly valued.

A five-minute walk from the port is the Donburiya Shichibee restaurant. I ordered a set meal featuring prime saba donburi. The dish includes cooked rice topped with fish slices and other ingredients and served in a donburi bowl.

Kei Aotani / Ryoko Yomiuri Publication
A ¥1,800 set meal including a bowl of rice topped with prime mackerel slices marinated in soy sauce, fish meat ball soup, a small dish, and pickled vegetables.

When served, I quickly noticed that the mackerel slices marinated in soy sauce were sashimi. I’ve heard that mackerel can have the parasite anisakis and eating it raw is dangerous.

“We freeze mackerel in a freezer at minus 60 C for at least 24 hours to eliminate anisakis, so you don’t have to worry,” the restaurant owner Toshikazu Shimizu assured me confidently with a smile. “The key is to soak the fish in a patented salt sauce before freezing. It reduces the distinctive bad smell and makes it possible to be served as sashimi.”

I then started to eat.

When I ate the sashimi alone, the part close to the skin was pleasantly chewy. The belly felt melty like otoro (a fatty part of tuna).

“Very good!” I said loudly. Shimizu broadly smiled, satisfactorily.

Each year from December to January, an event called Choshi Gokujo Saba Ryori Matsuri is held, offering set meals featuring prime mackerel at six restaurants, including Shichibee (reservations required).

I will come here again to experience a prime mackerel set, I thought to myself.


Japan Tourism is presented in collaboration with Ryoko Yomiuri Publication, which publishes Ryoko Yomiuri, a monthly travel magazine. If you are interested in the original Japanese version of this story, click here.