Japanese Spanish mackerel nigiri

Japanese Spanish mackerel (Sawara)

【Nigiri sushi: Shiromi】
What is Sawara?
Found across the country's coasts from southern Hokkaido to Kyushu and Okinawa, sawara is often caught in the Seto Inland Sea. Sawara is called by different names as it grows. Young fish of 30-40 cm are called yanagi. 40-50 cm are called sagoshi. 50-60 cm are called nagi, and that 60 cm or over are called sawara. It can reach large sizes up to 1 m in length.

Sawara is often thought of as a spring fish but its season can vary depending on the region. In the Seto Inland Sea, sawara comes from open seas to spawn. The character for sawara, “鰆” incorporates the character for spring (春), apparently from the phrase “you know it’s spring by the sawara”. Kan-sawara is enjoyed in the Kanto region starting in autumn. Those caught after December are especially delicious. In Wakayama, Sawara caught during the cherry blossom (sakura) season is called Sakura Sawara.

Sawara is a type of mackerel and it has a beautiful white flesh but without the reddish parts like a typical mackerel. It has a texture that melts in the mouth and a unique flavor where the skin meets the flesh. This is the secret to sawara's popularity. It does not have a strong taste but it is rich which is believed to be because they feed on sardines and Pacific saury.

By feeding on sardines and pacific saury, we can surmise from the content of fatty acids that make up the fat of the sawara. The fat content of sawara can be as high as 14% in early February and it has a high amount of Eicosapentaenoic acid and Docosahexaenoic acid compared with other fatty acids. The Docosahexaenoic acid is higher than sardines and pacific saury. Therefore, in addition to being good for brain activity, it is also good at preventing arteriosclerosis.

The tastiness of sawara can be understood from an extract of its muscle. It has 450 mg of nitrogen in every 100 g of muscle. This is as much as sea bream and yellowtail, meaning it has plenty of umami. When it comes to amino acids, it has as much histidine as mackerel. It has more taurine than sea bream. It is also plentiful in substances that give a rich taste such as inosinic acid, carnosine, carnitine and others. These are the substances behind the rich flavor of sawara.

What does Sawara (Japanese spanish mackerel) nigiri sushi taste like?
Japanese Spanish mackerel (Sawara) is a fish with a high water content; its flesh is delicate, tends to fall apart easily, and loses freshness quickly. For this reason, in the past, when transporting fresh Spanish mackerel over long distances, a board was placed under the fish and secured with a rope to prevent the flesh from deforming. Additionally, since Japanese Spanish mackerel caught in large quantities using nets tends to spoil easily, line-caught fish has traditionally been preferred for sashimi and sushi. As a result, Japanese Spanish mackerel was rarely served at sushi restaurants in Tokyo for a long time.

However, in recent years, the development of ikejime methods on board, advances in refrigerated logistics, and the northward shift of fishing grounds due to global warming have enabled a stable supply of high-quality Japanese Spanish mackerel. Consequently, it is now served more frequently at sushi restaurants and is becoming one of their signature offerings.

Although Japanese Spanish mackerel belongs to the mackerel family, it lacks the deep red hue typical of that group and is characterized by its translucent white flesh. It has a melt-in-the-mouth texture, and its distinctive flavor—particularly the umami found between the skin and the flesh—is considered its greatest appeal. While the flavor may seem mild at first, it is actually rich, and the umami deepens the more you eat it.

While delicious as sashimi, its umami is enhanced through aging or kombu curing when prepared for sushi, further highlighting its natural qualities. In particular, nigiri with the skin lightly seared adds a toasty aroma and the sweetness of the fat, making its tender texture stand out even more. Additionally, in major consumption areas such as Okayama, Kansai, and Shikoku, it is often lightly marinated in vinegar (sujime) before being made into sushi. In these cases, smaller fish that can be eaten skin-on are generally used.

Opinions vary regarding which cuts are best based on fat content. Generally, some consider the back and tail sections—where the flesh is firmer and less likely to feel overly heavy—to be the finest cuts, while many sushi restaurants value the visual appeal and richness of fat, making the belly section a prized choice. Overall, its mild flavor and the fact that it never becomes monotonous are key attractions.

Also called Spotted mackerel or Spanish mackerel.

【Temperature of vinegared rice (shari) and sushi toppings】
36℃/20～23℃

【Sawara trivia】
Kyoto and Fukui prefectures are major producers of Sawara (Spanish mackerel), but Okayama prefecture has the highest consumption rate in Japan, accounting for about 30% of the national total.

【Substitute fish】
Wahoo (Kamasusawara): Acanthocybium solandri (Cuvier, 1832)
Silver gemfish (Minamikagokamasu): Rexea solandri (Cuvier, 1832)
Queensland school mackerel: Scomberomorus queenslandicus Munro, 1943

【Related contents】
List of White flesh fish (Shiromi)