Battera and Oshizushi: Osaka’s Pressed Sushi Before Tokyo

Osaka invented pressed sushi centuries before Edo’s chefs ever shaped a piece of nigiri by hand — and the most precise proof of that priority is battera, a rectangle of vinegar-cured mackerel, sweetened rice, and translucent kelp whose exact origin can be dated to a single restaurant in Minami-Semba in the early 1890s. The form it crystallised, oshizushi, had been Osaka’s dominant sushi culture since at least the mid-Edo period, shaped by the city’s role as Japan’s rice and kelp entrepôt, its merchant demand for portable, giftable food, and a preservation logic that had nothing to do with the fresh-fish abundance of Tokyo Bay. Understanding why Osaka pressed rather than pinched its sushi is, in miniature, understanding why Osaka became Osaka.

Why we can tell you this — MICHI is written and edited in Osaka; our team can walk to Sushi Tsune in Tenjinbashi, stand in the Semba wholesale district where Yoshino Sushi still operates, and buy battera off the counter at Kuromon Market on any given morning. This article draws on the Japanese Ministry of Agriculture, Forestry and Fisheries’ regional cuisine records for Osaka, the Web Japan / Nipponia documentation of Yoshino Zushi’s hakozushi history, Kikkoman’s food-history archive on sushi’s evolution, and the Osaka Chuo Ward heritage panels on Semba’s commercial history. Where dates conflict between sources — the founding year of Sushi Tsune is given as both 1891 and 1894 in different records — we note the discrepancy rather than paper over it.

Pull a piece of battera apart with chopsticks and look at what you are holding. On top: a near-translucent sheet of shiroita konbu, pale jade, faintly sweet, shaved from the innermost core of dried Hokkaido kelp by a craftsman using a blade made in Sakai.

Beneath it: a fillet of mackerel, salt-cured and then steeped in rice vinegar until its flesh turns from translucent grey to an opaque, silvery white. Beneath that: a compact block of rice seasoned with kombu dashi and a touch more sugar than any Tokyo chef would dare use.

The whole thing was assembled in a wooden mold, pressed under a lid, then sliced into rectangles with a wet knife. It has been made this way, in this city, for well over a century.

That it exists at all — that this particular combination of ingredients, technique, and philosophy survived into the age of conveyor-belt sushi and overnight delivery of bluefin from Tsukiji — is not an accident of sentiment. It is the residue of a specific history: of geography, of trade routes, of a merchant class that needed food to travel, and of a city that built its identity around eating well rather than eating fast.

Why Did Sushi Begin as Fermentation, Not Fish?

The question of why Osaka pressed its sushi rather than hand-forming it cannot be answered without going back to what sushi actually was before anyone thought of putting raw fish on a ball of rice. The answer is: a preservation technology, not a cuisine.

Narezushi — the original form — is a dish of salt-cured fish and fermented rice, introduced to Japan in the 8th century and generally recognised as the first sushi. The fish was packed in salted rice and left to ferment for months, sometimes years.

The fish might be cured in salt for months or even years. The rice was not eaten; it was a fermentation medium, discarded once the fish was ready.

What you consumed was essentially a lactic-acid-preserved protein, pungent and funky, closer in spirit to a European aged cheese than to anything on a modern sushi counter.

References to nama-narezushi — partially fermented sushi, called nama-nare for short — appear around the fifteenth century. This was the first decisive shift: the fermentation period of namanare was shorter than that of earlier narezushi, and the rice used for fermentation was also eaten with the fish. With the invention of namanare, sushi changed from a preserved fish food to a food where fish and rice are eaten together.

The second shift was chemical. During the eighteenth century, vinegar gradually became the primary source used to create the characteristic sourness, reducing the time required for fermentation.

By the early nineteenth century, inspired by this use of vinegar and by accelerating the overall sushi-making process, non-fermented sushi had emerged. Rather than fermenting the fish, the rice itself was made slightly acidic by mixing in vinegar, creating the combination of vinegared rice topped with seafood that we know today.

This transition — from months-long fermentation to vinegar-seasoned rice — is what made modern sushi possible. But it produced two very different results in two very different cities, for reasons that had everything to do with geography and almost nothing to do with taste.

Why Did Osaka and Edo Develop Opposite Answers to the Same Problem?

By the early nineteenth century, both Osaka and Edo (present-day Tokyo) had arrived at the same basic insight: vinegared rice plus cured or fresh fish equals something people want to eat. What they did with that insight diverged completely, and the divergence was not arbitrary.

Edo sat on a bay. Modern nigiri as the world knows it emerged on Edo street stalls in the 1820s–1830s, most often credited to chef Hanaya Yohei (1799–1858), who perfected the technique around 1824 in Ryōgoku.

“Edomae” — meaning “in front of Edo” — referred to the fresh seafood caught directly from Tokyo Bay. The city was a construction site of the soul — a shogunal capital flooded with male migrant workers, samurai retainers, and craftsmen who needed food fast and cheap.

Wanting to serve sushi without long preparation times, Hanaya developed the nigiri-zushi method: sliced neta placed directly on top of vinegared rice balls, hand-moulded together at once. This new preparation method was a revelation.

Nigiri was, in essence, the world’s first successful fast food: made to order, eaten standing at a stall, gone in two bites. Edomae sushi is hand-pressed nigiri, invented in the 1820s as a street fast food, using rice seasoned with red vinegar (akazu) and designed to be eaten immediately.

The fish was raw because the bay was right there. The vinegar was red — made from sake lees — because that was what was available and what the flavour profile demanded.

Osaka had none of these conditions. It was not a coastal city in the same sense; it sat at the mouth of the Yodo River, connected to the sea but separated from deep-water fishing grounds.

More importantly, it was not a city of hungry male workers eating on the street. It was a city of merchants.

Even after the Edo period, when the political centre moved to Edo, Osaka remained a major economic and commercial centre thanks to its well-developed land and sea transportation infrastructure. Annual tax rice and specialty products from all over the country were collected in warehouses in Osaka, sold by merchants, and sent all over the country. Osaka, where ingredients from every region of Japan were commonly traded, received the name “The Kitchen of the Nation.”

The Semba district, the commercial heart of the city, was where this logic crystallised into food culture. Following the Winter Siege of Osaka in 1614, the Tokugawa family brought in experts in city development and craftsmen from all over Japan to rebuild Osaka Castle and revitalise the city. After that, inns, restaurants, money changers, clothing and hardware stores began springing up in the Semba area, and it flourished as the centre of Japanese economy and logistics.

The incentive of attracting and keeping well-paying customers encouraged chefs to improve their skills. Semba had a large merchant population.

These merchants would take their clients and customers out to restaurants to eat and talk business. This was the demand environment that shaped Osaka sushi: not a hungry dockworker grabbing two bites at a stall, but a merchant entertaining a client, needing food that was beautiful, portable, giftable, and good hours after it was made.

Edomae (Tokyo) sushi is hand-pressed nigiri, invented in the 1820s as a street fast food, using rice seasoned with red vinegar (akazu) and designed to be eaten immediately. Osaka-style oshizushi (hakozushi) is pressed into wooden molds, uses sweeter rice seasoned with kombu dashi, and was designed to be eaten hours later — originally as theater intermission food at Dotonbori. In Osaka sushi, all toppings are cooked or cured, never raw.

The wooden mold — the oshibako — was not a limitation. It was a solution.

Pressing the sushi compacted it, stabilised it, made it sliceable and stackable and transportable. A box of hakozushi could be carried across the city, presented as a gift, eaten between acts at the Kabuki theater, or served at a business dinner hours after preparation.

Raw fish on a rice ball could do none of these things.

Why Did the Oshibako Become an Art Form in Osaka?

The wooden mold had been in use in the Kansai region since at least the Muromachi period. By the mid-Edo period, Osaka emerged as the hub for hakozushi culture.

Renowned specialties like “saba no bōzushi” (pressed mackerel sushi) and “kodai no sugatazushi” (whole sea bream sushi) became iconic. But the transformation of pressed sushi from a practical preservation technique into something approaching visual art happened in one specific place: a shop in Semba called Yoshino Zushi.

In 1841, a well-established sushi shop in Osaka’s Senba district called Yoshino Zushi developed hako-zushi, with its different toppings and sandwiched insides arranged like a work of art. The idea came from Yoshino Torazo, the third owner of Yoshino Zushi.

What Torazo understood — and what distinguishes Osaka sushi from every other regional tradition — is that the mold is not just a shaping device. It is a canvas.

When you press multiple ingredients into a rectangular form and then slice it, you reveal a cross-section: a geometric mosaic of colour and texture that no hand-formed piece of nigiri can replicate.

Off comes the top of the box to reveal an astoundingly beautiful interior — it looks like a fabric woven with different colours of silk. The distinctively tasty ingredients making up this pattern are pale-pink crimson sea bream, auburn-coloured sea eel, bright red shrimp beside pieces of yellow omelet, and almost black kikurage mushrooms seen through the transparent flesh of sea bream.

This was not decoration for its own sake. In Osaka’s merchant culture, the presentation of food was a statement of commercial seriousness.

The Senba district, where Oyama’s shop is located, has been a flourishing centre of commerce in the middle of Osaka for centuries. The box sushi made there is nice to look at and delicious to eat, a good reason why it is considered a fashionable present to give to others.

Oyama says that business owners have patronised Yoshino Zushi since the early days.

During the Meiji period, Yoshino Sushi in Senba introduced boxed sushi made with high-quality ingredients like sea bream, shrimp, and conger eel. This compact, colourful sushi box, known as hakozushi, turned out to be perfect for quick meals during theater intermissions or as souvenirs. It gained immense popularity among the local community and soon became a beloved part of hospitality cuisine.

The rice itself was engineered for this purpose. Osaka sushi uses kelp stock (kombu-dashi) and a lot of sugar in its rice.

The extra sugar keeps the rice moist and prevents it from getting too dry, which is important because Osaka sushi is usually served cold. This is not a stylistic preference; it is a functional requirement.

Rice that dries out and hardens is useless in a gift box. Rice kept supple by sugar and dashi stays edible and pleasant for hours.

The sweetness that Tokyo sushi lovers sometimes find excessive in Osaka-style rice is not an aesthetic choice — it is the taste of a food engineered to travel.

Why Did a Portuguese Word End Up in the Name of Osaka’s Most Famous Sushi?

Here is where the story becomes genuinely strange, and where the layered “why” opens a trapdoor into a history most visitors never suspect.

Battera — the pressed mackerel sushi that is now the most recognisable single item in Osaka’s sushi vocabulary — takes its name from the Portuguese word bateira, meaning a small boat. This is not a coincidence or a folk etymology. It is a direct trace of Japan’s sixteenth-century contact with Portuguese traders, whose linguistic fingerprints are scattered across the Japanese language in words like pan (bread, from pão), tempura, and castella sponge cake.

The mechanism of the naming is documented. It is said to have been devised in 1891 (Meiji 24) by Naka Tsunekichi, the founder of “Sushi-tsune” in Minamisemba, Osaka.

The original topping was konoshiro (gizzard shad), which was abundantly landed in Osaka Bay; because a single fillet resembled a small boat, the dish was named after “bateira,” the Portuguese word for a small boat. When the price of konoshiro later rose, the leading role shifted to the more affordable mackerel, settling into its present form.

The Japanese Ministry of Agriculture’s regional cuisine records give the founding year as 1894 rather than 1891 — a three-year discrepancy that likely reflects the difference between when Sushi Tsune was established and when the specific battera form was perfected. At the time, Sushi Tsune was selling oshizushi made with konoshiro, which was commonly caught in Osaka Bay.

Due to its popularity, the traditional method using a cloth became insufficient for production, so a wooden, boat-shaped mold was used instead. Customers reportedly referred to the mold as “bateira,” a Portuguese word meaning “boat,” which evolved into “battella” and then into “battera.”

Why konoshiro? Kohada is the juvenile form of konoshiro, caught wild along Japan’s Pacific coast from southern Hokkaido to northern Kyushu, favouring shallow, coastal waters where it swims in schools.

In the late nineteenth century, Osaka Bay was rich with them — a cheap, abundant, silver-skinned fish that took well to salt-and-vinegar curing. The same fish, in its younger form as kohada, was simultaneously becoming the signature topping of Edomae nigiri in Tokyo, where Kyoto and Osaka often used mackerel in their pressed sushi, while Edo offered the smaller and easy-to-eat kohada.

Two cities, one fish, two completely different preparations — the divergence in miniature.

When konoshiro prices rose — as they did, as any commodity rises when demand outpaces supply — Naka Tsunekichi or his successors switched to mackerel. It was gradually replaced by the inexpensive mackerel, and the square box shape was also used for the pressed molds.

The name battera stayed, even though the boat-shaped mold that gave it the name was replaced by a rectangular one. The word had already attached itself to the form, the flavour, the idea.

Language, like food, is conservative.

Why Does the Kelp Matter as Much as the Fish?

Ask a Tokyo sushi lover what makes battera distinctive and they will probably say the mackerel. Ask an Osaka sushi maker and they will say the konbu.

The shiroita konbu — literally “white-board kelp” — that lies across the top of a piece of battera is not a garnish. It is a structural and flavour-critical component, and its production is itself a small industrial miracle rooted in Osaka’s position as Japan’s kelp-processing capital.

Shiroita kombu is a pale, thin sheet of kombu that remains as the central core after the outer and inner layers of a dried kombu strip have been shaved away to produce oboro kombu and related products. The core is cut to standardised rectangular sizes and sold for culinary use. The same material is also known as battera kombu, after its signature application.

The thin sheet is laid across the top of battera and, by extension, across other forms of oshizushi. Producing shiroita kombu is hand craft: a dried kombu strip is first softened by soaking in vinegar; an artisan then shaves it, layer by layer, with a specialised plane known as an akita.

The connection between this ingredient and Osaka is not incidental. Hokkaido is renowned for its kelp, traditionally transported during the Edo period on Kitamae-bune ships to processing sites at major ports.

Osaka was one of those ports — the dominant one. The city’s knife-making tradition, centred on Sakai, provided the specialised blades needed to shave kombu to translucent thinness.

Sakai was home to knife-making techniques, which allowed for kombu to be shaved using special knives. This led hand-processed oboro kombu and tororo kombu to flourish.

Oboro kombu is made from kombu produced in Hokkaido, then shaved by a master artisan using a Sakai knife.

The shiroita konbu performs several functions simultaneously. Mackerel and boiled kombu are soaked in vinegar in advance, so it improves storage stability and suppresses fishy odours.

It also adds a layer of glutamate-rich umami that amplifies the mackerel without competing with it, and it gives the finished piece a visual elegance — that jade-green translucency — that no other ingredient could provide. This exceptionally rare kombu is crafted from the core centre of dried kelp, meticulously shaved with a specialised akita blade until translucent.

Renowned for its refined texture and subtle umami, it is traditionally used in pressed sushi and prized for its ability to impart both visual elegance and nuanced flavour.

The full supply chain of a single piece of battera, then, runs from the kelp beds of Hokkaido, down the Sea of Japan coast on Edo-period cargo ships, through the knife workshops of Sakai, into the processing houses of Osaka, and onto the wooden mold of a sushi maker in Tenjinbashi. It is a dish that could only have been invented in a city that sat at the intersection of all those routes.

Why Did Oshizushi Survive When Nigiri Conquered the World?

The Great Kanto Earthquake of 1923 is one of the hinge points in sushi history. It killed over 100,000 people in Tokyo and the surrounding region, destroyed the city’s infrastructure, and — as a secondary consequence — scattered Tokyo’s sushi chefs across Japan.

There are various theories as to when authentic Edomae nigiri sushi became popular in Osaka, including that it was after the Meiji Restoration or the Great Kanto Earthquake. The earthquake accelerated the national spread of nigiri, which had already been gaining ground since the Meiji period as Japan modernised and Tokyo’s cultural influence expanded.

By the mid-twentieth century, nigiri had become the default meaning of the word “sushi” in most of Japan and, eventually, in most of the world. The pressed forms — oshizushi, battera, hakozushi — retreated into regional identity, into department store food halls, into the category of “traditional” food that people ate on special occasions or brought home as omiyage from Osaka.

Why did oshizushi survive at all? Several reasons, none of them sentimental.

First, the practical advantages that created it never disappeared. Oshizushi is one of Japan’s regional sushi nurtured by culinary traditions dating back to the Edo period, and its greatest appeal lies in the beautiful layered cross-section created by pressing rice and toppings in wooden molds.

Beyond its striking appearance, the compression process gives it a firm yet pleasant texture, while providing excellent portability and preservation. In a city where food gifting remains a serious cultural practice — where the depachika (department store basement food hall) is a genuine institution — a sushi that travels well and looks spectacular in a box has a permanent market.

Second, Osaka’s identity politics. The city has always defined itself in opposition to Tokyo, and its food culture is one of the primary arenas of that self-definition.

Whereas hand-formed nigiri sushi developed in Edo, the Kansai region cultivated a culture of pressed sushi made with wooden molds, and battera can be regarded as a representative example. To eat oshizushi in Osaka is not merely to eat a regional dish; it is to make a statement about where you stand in the Tokyo-Osaka cultural argument that has been running for four centuries.

Third — and this is the reason that matters most to the long-term survival of any food tradition — the craft is genuinely difficult and genuinely rewarding. According to shopkeeper Takuji Hashimoto of Yoshino Sushi, the secret to making delicious oshizushi is in the time-consuming process of preparing the ingredients.

“For example, we salt the sea bream and leave it to rest for a day to bring out its umami flavour, while our shiitake mushrooms are cooked for five hours and then left to sit for a day to let the flavours blend.” A food that requires this level of preparation cannot be industrialised without losing what makes it worth eating. That difficulty is a form of protection.

The Sushi Tsune Story: Closure, Revival, and What It Means

The most poignant episode in battera’s modern history is also the most instructive. Sushi Tsune — the restaurant where battera was invented in the 1890s, the house that Naka Tsunekichi built — closed its doors at some point in the twentieth century. The lineage appeared broken.

Sushi Tsune, the originator of battera, once closed its doors, but in 2016, the fourth generation of the family revived the restaurant. After a 30-year closure, the fourth generation now runs the shop.

He says his wife is a direct descendant of the founder. The restaurant reopened in its current location near Osaka Tenmangu Shrine, with six counter seats and a menu built around the dish that made the name.

This is not a story of heritage tourism or nostalgic revival for its own sake. It is a story about what happens when a specific technique, attached to a specific place and a specific family, nearly disappears — and what it takes to bring it back.

The fourth-generation chef did not open a museum; he opened a restaurant. The chefs at Sushitsune have inherited their traditional techniques and flavours from a long-standing establishment that was founded during the Meiji Era, spanning up to the fourth generation.

While preserving their traditional skills, they also incorporate new ideas.

The Michelin Guide noticed. Sushi Tsune now holds a Bib Gourmand designation — recognition that the food is exceptional value, not merely historically significant. The distinction matters: a Bib Gourmand is awarded for what is on the plate, not for what is on the wall.

Why the Rice Is the Argument

There is a technical detail about Osaka sushi rice that deserves more attention than it usually gets, because it encodes the entire philosophical difference between the two sushi traditions.

Edomae rice is seasoned with akazu — red vinegar made from sake lees — which gives it a yellowish tinge, a deeper umami, and a pronounced acidity. It is designed to be eaten within minutes of being made; the vinegar is aggressive and forward, calibrated to the immediacy of the nigiri experience.

Osaka rice is seasoned with rice vinegar, kombu dashi, sugar, and salt. Osaka sushi uses kelp stock (kombu-dashi) and a lot of sugar in its rice.

The extra sugar keeps the rice moist and prevents it from getting too dry, which is important because Osaka sushi is usually served cold. They add dashi to keep everything in harmony and prevent spoilage, thanks to kelp’s natural preservative qualities.

The sugar is not a sweetener in the dessert sense. It is a humectant — a substance that retains moisture.

Combined with the glutamates in kombu dashi, it creates a rice that stays supple and flavourful for hours, that does not dry out or harden when cold, and that provides a gentle, rounded base against which the acidity of the cured fish can register clearly. It is rice engineered for time, not for immediacy.

This is the deepest structural difference between the two traditions. Nigiri is a present-tense food: it exists in the moment of its making and must be eaten then.

Oshizushi is a food that improves with a little waiting — the pressing compacts the flavours, the vinegar continues to work on the fish, the kombu releases its umami into the rice. What sets battera apart from other sushi styles is its texture and taste.

The compression of the ingredients creates a dense, chewy texture that perfectly complements the tender, slightly sour mackerel. You cannot rush that compression.

You cannot hand-form it. The mold is not a shortcut; it is the point.

Why the Discerning Traveller Should Eat This Before Anything Else in Osaka

The affluent traveller who arrives in Osaka having already eaten omakase in Tokyo faces a specific risk: mistaking familiarity for quality. Nigiri is the global default for “serious sushi.” It is what the world’s best-known sushi restaurants serve.

It is what the Michelin stars cluster around. To arrive in Osaka and seek out the same thing — to look for the best nigiri counter rather than the best oshizushi shop — is to miss the point of being here entirely.

Oshizushi and battera are not lesser versions of nigiri. They are a parallel tradition that predates nigiri by centuries, that solved different problems with different tools, and that produces a flavour and texture experience that nigiri cannot replicate.

Kansai oshizushi transcends simply eating sushi — it is a unique culture shaped by wooden molds and heavy stones. Unlike the glamour of Edo-style box sushi or hand-pressed nigiri, its greatest allure lies in the beauty of its cross-sections and the nuanced flavours of each layer.

There is also a temporal argument. The craft of making oshizushi — the hand-shaving of shiroita konbu, the precise salt-and-vinegar curing of mackerel, the construction of a hakozushi mosaic that reveals its geometry only when sliced — is genuinely endangered.

The skill of making hakozushi has been declining, due to the time and effort compared to regular sushi. It is a traditional technique, which dates back centuries and is now seen more as a luxury kind of sushi.

The number of shops in Osaka that make oshizushi from scratch, by hand, using traditional methods, is small and shrinking. The supermarket versions — vacuum-packed, machine-pressed, available at every convenience store — are not the same thing.

They are the ghost of the idea.

To eat at Sushi Tsune or Yoshino Sushi is not nostalgia tourism. It is the act of encountering a living craft at a moment when its survival is genuinely uncertain. The flavour is the argument, but the context is the reason to care.

Consider also what battera tells you about Osaka that nothing else does quite so efficiently. Osaka, where ingredients from every region of Japan were commonly traded, received the name “The Kitchen of the Nation.” A single piece of battera contains Hokkaido kelp, Kansai mackerel, Osaka-processed shiroita konbu, and rice seasoned with dashi that encodes centuries of kombu-trading history. It is a compressed archive of the city’s commercial geography, pressed into a rectangle and sliced for your plate.

The Portuguese word in its name is the final flourish. Japan closed its borders to most foreign trade in 1635 and did not reopen them until 1853.

The word bateira entered the Japanese language during the brief window of Portuguese contact in the sixteenth century, survived two centuries of isolation, and re-emerged in the name of a sushi invented in Meiji-era Osaka. Language preserves what history tries to erase.

So does food.

Frequently Asked Questions

Q: What is the difference between battera and regular oshizushi?
A: Oshizushi is the broad category — any sushi pressed in a wooden mold. Battera is a specific type of oshizushi made with vinegar-cured mackerel (shime-saba) and shiroita konbu (white kelp sheet) pressed over vinegared rice.

Saba-zushi and battera are often confused, but they are quite different. Saba-zushi is made with half a mackerel, wrapped in vinegared rice using a bamboo mat to form a stick-shaped sushi.

Battera, on the other hand, uses thinly sliced mackerel; the mackerel, along with kombu and vinegared rice, is packed into a box-shaped mold and pressed to form a pressed sushi.

Q: Where was battera invented, and can I still visit that restaurant?
A: Minamimorimachi Sushi Tsune, established in 1891, is renowned as the birthplace of battera. Located near Osaka Tenmangu Shrine, the restaurant has been serving authentic sushi for over a century, preserving traditional techniques and flavours.

The restaurant closed for approximately 30 years and was revived in 2016 by the fourth generation of the founding family. It now holds a Michelin Bib Gourmand.

Reservations are strongly recommended; the counter seats only six people.

Q: Why does Osaka sushi rice taste sweeter than Tokyo sushi rice?
A: The sweetness is functional, not merely stylistic. The rice is sweeter than Edomae (more sugar, seasoned with kombu-dashi) specifically because Osaka sushi was designed to be made in advance and eaten later, often between acts at Dotonbori theater. The sugar acts as a humectant, keeping the rice moist and palatable for hours after pressing — a necessity for a food designed to be gifted, transported, and eaten cold.

Q: Is shiroita konbu the same as regular kombu?
A: No. Shiroita kombu is a pale, thin sheet of kombu that remains as the central core after the outer and inner layers of a dried kombu strip have been shaved away to produce oboro kombu and related products. It is a byproduct of the oboro kombu shaving process, hand-crafted using Sakai-made blades, and is sometimes called “battera kombu” after its primary use. Its translucency, subtle sweetness, and umami depth are specific to this processing method and cannot be replicated with standard kombu sheets.

Q: Did oshizushi influence the development of nigiri sushi in Tokyo?
A: The historical record suggests it did. One origin story for nigiri focuses on a peddler named Hanaya Yohei, who moved from place to place selling oshizushi, a form with cooked or cured fish pressed into a box mold.

He opened a stall in a crowded area between two famous temples in 1810, where customers gathered to watch him prepare the food. To speed up the show, Yohei began to use fresh raw fish, easily available from Tokyo Bay.

On this reading, nigiri is not the opposite of oshizushi but its acceleration — the same logic of fish-plus-vinegared-rice, stripped of the mold and the waiting time.