What is moshio? The golden salt of the Seto Inland Sea, revived from a Kofun-period method

Many people know the word moshio (藻塩) only from poetry. The phrase "burning moshio" turns up again and again in the Manyoshu (万葉集). The sight of seaweed being burned on the shore to take salt from it was an everyday one for people in Japan more than a thousand years ago.

Then moshio stayed buried in history for a long time. What brought it back into the present was a single piece of pottery found on a small island in the Seto Inland Sea.

A revival that began with excavated pottery

On Kami-Kamagarijima (上蒲刈島), in Kure, Hiroshima Prefecture, salt-making pottery from the Kofun period (古墳時代) has been excavated. It is the trace of seawater boiled down in earthenware to take out the salt. That means salt has been made on this island for about 1,500 years.

Working from that discovery, Kamagari Bussan, on Kami-Kamagarijima, reconstructed the ancient "moshio-yaki" as a method for the present day. Seawater from the Seto Inland Sea is boiled down together with the essence of the seaweed hondawara (ホンダワラ). The method was inferred from written records and from the pottery, and "Amabito no Moshio" is said to be what came out of that trial and error.

In a place where salt-making had once died out, the findings of archaeology come back to the table as a seasoning. It is a salt with a history few others share.

Why the finish is something like dashi

Taste moshio and a soft savoriness stays behind after the saltiness.

The reason is hondawara. Seaweed contains savory compounds, glutamic acid among them, and boiling the salt down together with that extract dissolves them into the crystals. The pale golden color comes from the seaweed as well.

"Salt, and yet there is a hint of dashi in it." That quality makes moshio a salt for the last pinch. It gives an ingredient its saltiness and lays the savory groundwork at the same time.

Amabito no Moshio: Kamagari Bussan

"Amabito no Moshio" is the best-known moshio, made by Kamagari Bussan on Kami-Kamagarijima. It uses only seawater from the Seto Inland Sea and hondawara, and is finished in a pale golden color.

The scene of "burning moshio" sung about in the Manyoshu, brought back as a working method after salt-making pottery came out of the ground. You can check the memory of the salt people in Japan tasted more than a thousand years ago in your own kitchen.

Ways to enjoy moshio

• As dipping salt for tempura. The sweetness of the ingredient and the savoriness come up together
• A pinch on sashimi of white-fleshed fish, in place of shoyu
• To finish yakitori or grilled rice balls
• Swap it for the salt in an onigiri and taste the difference in savoriness
• To season simple things such as boiled eggs and warm vegetables

Try it first on tempura, or in a plain salted rice ball, and taste what savory salt means. The memory of an ancient sea comes back in a single pinch.

Frequently asked questions

What is moshio?

It is a salt made by one of the oldest salt-making methods in Japan, boiling down seawater together with the essence of a seaweed called hondawara. Because it carries savory compounds from the seaweed it takes on a pale golden color, and although it is salt it leaves a finish something like dashi.

How does moshio differ from ordinary salt?

Ordinary salt is made from seawater alone, while moshio is boiled down with seaweed extract added. That brings in amino-acid savoriness, and the edge of the saltiness feels softer. The color is not white either, but a pale beige to golden.

What dishes suit moshio, and where can I buy it?

It especially suits dishes where salt is used for dipping, such as tempura, sashimi of white-fleshed fish, and yakitori. "Amabito no Moshio" from Kure, Hiroshima Prefecture (Kamagari Bussan) is a leading example, and it can be bought through online shops including Amazon.