Tsukudani: A Traditional Japanese Preserved Food

It is only recently that vegetables, fruit, fish and shellfish have become available year-round. Until the advent of freezing and logistics technologies, we could only eat what was available at that time of year.

If you live in a warm location where fresh food is always available, you could live off seasonal produce alone, but there are many places in the world where securing ingredients is difficult for long periods of the year due to climate and other reasons. Preserved foods were developed to cope with this. Fresh ingredients are prepared in advance by processing them using techniques such as fermentation, drying and smoking. Today, many preserved foods are being adapted and produced in countries all over the world.

We are on a journey to explore preserved foods, wisdom for everyday life that support the foundations of culinary culture.

In Part 2, we delve into tsukudani, food preserved by boiling in soy sauce, which appeared in the Edo period (1603–1867) of Japan’s history.

▶Part 1: Umeboshi (Pickled Plums) — Azuma Noen, Wakayama Prefecture

▶Part 3: Himono (Dried Fish) — Maruaka Shoten, Yushima, Tokyo

Tsukudani is small fish and shellfish boiled in soy sauce and sugar. There are many theories about its origins but from its name, there can be little doubt that it traces back to Tsukudajima (Chuo-ku, Tokyo).

Tsukudajima was formed around 400 years ago by filling in a tidal flat at the mouth of the Sumida River. Several dozen skillful fishermen from Tsukuda, a village in Settsu Province (Nishiyodogawa-ku, Osaka) settled there on the instructions of Tokugawa Ieyasu, the founder and first shōgun of the Tokugawa Shogunate. The small fish and shellfish they preserved by boiling in salted water for when they were not fishing or to eat onboard was the original tsukudani. After that, the original tsukudani spread from Edo (present-day Tokyo) across Japan, but why did Ieyasu call the Tsukuda fishermen to the area in the first place?

The answer dates to the Honnō-ji Incident (June 1582), when daimyō Oda Nobunaga was defeated by the rebellion of his samurai general, Akechi Mitsuhide. Ieyasu, an ally of Nobunaga, was in Osaka at the time and found himself in a predicament. He was helped to escape by Tsukuda’s village headman, and given the original tsukudani as provisions for the journey . It seems Ieyasu may have invited the fishermen from Osaka to repay the kindness. The tsukudani must have been exceptionally delicious.

Nihonbashi Funasa was established in 1862, at the end of the Edo period. At the time, Sakichi, the founder, who was in the business of selling grilled small carp on skewers, washed ashore on Tsukudajima during a fishing excursion. There, he learned the method for boiling small fry in salted water and, after returning home, came up with the idea of boiling small fish in soy sauce. When he sold this around the city, it became wildly popular. In other words, modern-day tsukudani, boiled in soy sauce, originated here at Funasa.

It keeps well, can readily be carried around, and is the perfect to eat as an accompaniment to steamed white rice. During the Meiji period (1868–1912), tsukudani was distributed as military rations and after the war, it became entrenched as an everyday food of the people.

One hundred and fifty years since its founding, the company is today led by Miyauchi Yu-san (born 1975), the fifth-generation successor of the founder.

One thing that greatly affects the taste of tsukudani is maintaining the quality of the tare (sauce).

“It is said that if there was ever an earthquake or fire, one was to save the tare, even if it meant leaving all other possessions behind,” says Yu-san. This precious sauce has been kept topped up from almost 60 years ago, when the method was fixed by the third- generation leader.

Kombu (kelp), shrimp, clams, gobō (burdock root) and other ingredients are placed in separate pots and boiled in three kinds of soy sauce and two kinds of sugar, among other things, then the tare is added and they are boiled some more. Once they are thoroughly cooked, the remaining liquid is strained off and returned to the precious tare barrel. They do this over and over.

“For instance, when the shrimps are plump, the remaining liquid becomes more viscous, and if placed back in the barrel in the same proportions, the tare will by heavy. When I use this sauce, the finished product will be stiff and leach salt, so you always need to make little adjustments.”

The secret tare is a reduction of extracts of vegetables, fish and shellfish. A lick of it was thick and deeply flavored. Just by itself, it would have made steamed rice delicious.

I followed the process for the production of gobō tsukudani, a flagship product since the time when Tokyo was still Edo.

A mountain of fresh gobō was added to a 70-liter pot containing soy sauce. Then sugar and the secret ingredient, chili, was added. The secret ingredient depends on the tsukudani being prepared: it may be red sake, ginger or starch syrup.

The heat is another important point. A very strong heat, 25,000 kilocalories, is used at the start. This is reduced gradually when the tare is added. Once boiled down, the gobō no longer has any of its initial ashy color. After about an hour, the tsukudani is taken from the pot at just the right time.

The spacious factory contains only pots, barrels, ingredients and seasonings

The inside of the factory is simple and orderly, but there is one tool that is essential to the production of tsukudani. The foreman, Sakata-san, can be seen peering into it in the photo on the right. It’s a Brix meter, which measures the viscosity of liquids and tells you the thickness of the tare and when it is finished simmering with an analog value. That value is, of course, a company secret.

When it is just finished cooking, the gobō tsukudani gives off a soy sauce smell, has a texture and is soft. I had the great privilege to be able to sample it, which is the very definition of a side benefit.

At 70°C, the just-cooked tsukudani is cooled to 20°C in a cooling room then packed immediately.

Funasa’s Edomae tsukudani is salty.

The soy sauce and tare soak in so much they make it salty. “We sometimes get complaints from new customers that it is too salty.” [Laughs] But this almost stubbornness in seasoning stems from the fact that Funasa is such a long-established store.

The photos above are konbu (kelp), gobō (burdock root), opossum shrimp, clam and eel. They are the most staple of staples, and have legions of fans throughout Japan.

Tsukudani with steamed white rice. The compatibility of this iron-clad combination is rivaled or even surpassed by that of ochazuke (rice with green tea poured over it). You could eat bowl after bowl of ochazuke made with Nihonbashi Funasa’s dashi stock, which is made from bonito and kombu.

“Tsukudani can be used in all sorts of recipes, you know. For example, add the kombu to pasta, or slice up the gobō and steam it with other ingredients as takikomi gohan. Being salty is not its only benefit.”

Besides these staple products, the lineup is wide, with lotus root in autumn and winter and raw nori (laver) in winter and spring, among others. I was not aware that there was a seasonal tsukudani for every season.

Funasa is always busy researching new ingredients that might be suitable for tsukudani.

“Recently, our foie gras offering was a huge hit. Its richness is the perfect accompaniment to champagne and wine. On the other hand, the red king crab was not a success. Once the crab meat had been boiled down, we were left with about 50 grams. So how much would we have needed to charge for it?” [Laughs]

Funasa is also proud and in high spirits about the potential of giving fruit the tsukudani treatment. It is encouraging to know that long-established stores are keen to take on new challenges.

https://www.funasa.com/