Where "murasaki" was made: Tsuchiura, and Shibanuma Shoyu Jozo's "Shiho," brewing since 1688

Here is the answer first. Inside a sushi restaurant, the word used for shoyu (soy sauce) is murasaki (紫), meaning purple. When the person behind the counter says "murasaki," they mean shoyu. Plenty of people know that much. But why purple? The pool of it in the dish is a brown so dark it may as well be black.

This article sets out what the word means, then lays out three accounts of where it came from, each with its evidence and its limits. Related sushi shorthand - agari, gari, namida - comes in along the way.

What "murasaki," the sushi word for shoyu, means

The word used for shoyu inside a sushi restaurant is murasaki. It means the shoyu you dip sashimi and sushi into. Nothing more, nothing less.

More precisely, it is one of the fucho (符丁) of the sushi and dining trade. Fucho are the in-house words that the people working in a shop use with each other - shorthand, effectively. They were not meant to be spoken to the customer; they were names that worked inside the shop.

So "murasaki" comes down to this:

• Meaning: shoyu
• Character: fucho of sushi restaurants and dining houses, a trade word
• Use: originally between the people working there. Customers overheard it, and it spread as a word that sounds like a sushi shop

It makes more sense as a word bound to a particular kind of place than as a dictionary synonym for shoyu.

As for why shoyu is called murasaki, no explanation has been settled on. Several are offered, and the one closest to the sushi restaurant itself is the fucho account, which comes next.

The account that it spread as sushi-shop shorthand

The sushi restaurants and dining houses of Edo had their own trade vocabulary for talking among the staff: a single short word for a fish, a tool, a move.

These are the well-known ones.

• Agari: tea (from the tea served at the end)
• Gari: ginger (from the sound of biting it)
• Namida: wasabi, literally tears
• Gyoku: egg (from the character for "jewel" in tamago)
• Shari: vinegared rice (said to liken the grains to Buddhist relics)
• Tsume: the reduced shoyu glaze
• Murasaki: shoyu

Set out like this, murasaki clearly is not an outlier among the sushi words for things. One item in a shop's vocabulary reached the customers' ears and carried on out into the world as a word that sounds like sushi. That is the least strained way to describe it.

Because it was never a word for customers to say, people do point out that asking for "murasaki" from the customer's seat today can sound a little like showing off. Knowing what the word means and using it yourself are two different things, and that is about the right distance to keep.

The account that it names the color itself

The other account told often is that the name simply describes the color.

Shoyu looks jet black, but in certain light it reads as a reddish brown with purple in it. Spread thin in a small dish, that deep red was called purple - so the reasoning goes. Against the white plate of a sushi restaurant, or the green of the bamboo leaf laid under sashimi, the color really does sit closer to purple than to black.

It takes "murasaki" at face value, as a color, which makes it easy to remember.

The account that purple was the color of high rank

The third takes the name as a comparison of worth.

Purple was once a color only those of high rank could wear. There was likewise a time when shoyu was not something ordinary households used freely. A precious thing was called by a noble color. Because this overlaps with the period when shoyu consumption in Edo rose sharply, the reading gets cited often.

Which one is right has not been decided. But behind murasaki settling in as the sushi word for shoyu, there was at minimum a shop that used it as its own word, and that much is safe to assume. Shoyu as the meaning, shop shorthand as the likeliest origin: that is enough to hold on to.

Shoyu country was not only Choshi and Noda

A short detour from the sushi counter to the places the shoyu came from, the shoyu that got called murasaki in the first place.

Ask where shoyu is made in Kanto and the answer is Choshi and Noda, both in Chiba. In the Edo period, though, another name stood beside them: Tsuchiura, in Ibaraki Prefecture.

Tsuchiura was a water-transport town on Lake Kasumigaura. Soybeans and wheat came in; the finished shoyu went out to Edo. Being able to do both by water is given as the reason brewing took hold here. Choshi, Noda and Tsuchiura together were spoken of, for a time, as the great brewing districts of Kanto.

In national name recognition, Tsuchiura has fallen far behind the other two. The brewery, though, is still there.

"Shiho," from a brewery running since 1688

Shibanuma Shoyu Jozo in Tsuchiura was founded in 1688. Across more than 330 years it has kept brewing in kioke (wooden barrels).

Its flagship is called "Shiho" (紫峰). The name comes from another name for Mount Tsukuba, which the brewery looks out on. That a mountain in shoyu country carried a name touching on the very word murasaki is almost too neat.

The taste is a crisp Kanto koikuchi, thick with savory depth. It is one bottle that shows what the shoyu of Tsuchiura, the shoyu behind Edo's sushi and Edo's dinner tables, was actually like.

How to enjoy Shiho

• Sushi and sashimi: as dipping shoyu. Try it plain first and look at the color and the scent
• Simmered dishes: the savory depth is strong, so even a little draws a clear outline
• Teriyaki: poured over at the finish, it changes both the gloss and the body
• Egg over rice: the plainest way to taste what koikuchi does
• Chilled tofu: the blander the ingredient, the more the quality of the shoyu shows

Follow the word murasaki back and you arrive at the shop shorthand of Edo, and at the history of the places that supplied it. A single short word passed across a counter is that history of a seasoning, in miniature.

Frequently asked questions

What word is used for shoyu inside a sushi restaurant?

"Murasaki" (紫), the word for purple. It is one of the fucho, the shop shorthand long used in sushi restaurants and dining houses, in the same family as agari (tea), gari (ginger) and namida (wasabi). It is generally explained less as a description of the color in the dish than as a name used inside the shop that simply stuck.

Why is shoyu called "murasaki"?

There is no settled explanation. The account told most often is that it was shop shorthand in the sushi restaurants and dining houses of Edo, and that it spread to the public along with agari, gari, namida and gyoku. Others hold that shoyu can look purplish depending on the light, or that in an age when purple signified high rank, a costly seasoning was named for a costly color. None of these has firm backing.

Besides murasaki, what other sushi-shop words are there?

Well-known ones include agari (tea), gari (ginger), namida (wasabi), gyoku (egg), shari (vinegared rice), tsume (the reduced shoyu glaze) and geso (squid tentacles). They began as in-house words passed between the people working behind the counter, not words meant for customers to say.

Is it all right for a customer to say "murasaki" at home or at a sushi restaurant?

There is no rule against it, but since these began as in-house words of the sushi and dining trade, using them as a customer can sound like showing off. Guides usually suggest that asking for "oshoyu" at the counter comes across more naturally.

Where in the Kanto region is shoyu made?

Choshi and Noda, both in Chiba Prefecture, are the best-known names. In the Edo period, though, Tsuchiura in Ibaraki Prefecture was counted with them as one of the great brewing districts of Kanto. Being able to move raw materials and finished shoyu by water across Lake Kasumigaura is said to be why Tsuchiura grew into a shoyu town.

Where can I buy shoyu from Tsuchiura?

Shibanuma Shoyu Jozo, founded in 1688, is still in Tsuchiura and still brews in kioke (wooden barrels). Its flagship koikuchi shoyu, "Shiho," can be bought through online retailers including Amazon. The savory depth is strong, so a little goes a long way, whether as a dipping shoyu for sushi and sashimi or in simmered dishes.