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Is Nigiri sushi made by a Master Really Transparent?!

A photo of shari — There is a moderate amount of space between the grains of rice.

“Sorry to keep you waiting,” says the sushi chef as he places a nigiri sushi in front of you, pieces of rice falling out. You may be served this kind of nigiri sushi at restaurants that have lines out the door. Of course, nigiri sushi that falls apart before it reaches your lips is a no-go.

Good nigiri sushi looks solid, but the rice naturally falls apart when you put it in your mouth. Secondly, the loosened rice absorbs the saliva that has the flavor of the topping, and does not make your mouth sticky.

On the other hand, if the rice is pressed tightly, it does not absorb the saliva. The taste of the toppings continues to linger in your mouth and gradually becomes a nuisance. In short, when they press the sushi, the surface is firmly pressed, but the inside is fluffy. This is the perfect way to press sushi.

At first, they will be too focused on the shape, their fingers will be too tense, and they will be pressing too hard. Once they relax their fingers and get a sense of the subtle pressure, they will be a full-fledged sushi chef. It is said that they should press the shari as if they were wrapping it in air.

For example, shari pressed for gunkanmaki should be hard enough to crumble after being placed on their index finger for five seconds. For nigiri sushi, it should be hard enough to sink a few millimeters when placed on a plate under the weight of the topping.

A master sushi chef is at the next level, and it is said that “nigiri sushi made by a master can be seen through when held up to the light.” He holds the sushi very gently. And it doesn’t lose its shape.

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Revision date: June 13, 2025

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Why are the prices at high-end sushi restaurants and conveyor belt sushi restaurants so different?

Conveyor belt sushi restaurants and high-end sushi restaurants in areas like Ginza both serve sushi, but they differ significantly in their roles and the quality of the experience they offer.

The most obvious difference is the price range. Conveyor belt sushi offers dishes starting at 100 yen per plate, making it affordable and popular among families and students. In contrast, high-end sushi restaurants primarily offer “omakase” courses, which can cost between 10,000 and 50,000 yen per person. These establishments are often chosen for special occasions or business entertaining, where customers seek an extraordinary experience.

The serving style is also contrasting. At conveyor belt sushi restaurants, the self-service style where sushi is served on a conveyor belt is the norm. Recently, touch-panel ordering and high-speed conveyor belts have been introduced to prioritize efficiency and speed. In contrast, high-end sushi restaurants primarily use a counter-style setup where chefs prepare each piece of sushi by hand and serve it directly to customers. Sushi is not merely a meal but an experience of “once-in-a-lifetime” interaction between the chef and the customer.

At the core of this “experience” lies the sushi chef’s observational skills and conversational abilities. Chefs at high-end sushi restaurants constantly observe customers’ eating progress, expressions, and how much they drink. They make split-second judgments about whether the sushi is being enjoyed, the timing for the next piece, and the customer’s hunger level, all while serving dishes at an impeccable pace. They do more than just serve sushi; they may also briefly explain the origin of the ingredients or the preparation process, or engage in conversation to lighten the mood. This ability to maintain the perfect balance—neither too much nor too little—while giving customers a sense of comfort and familiarity is a testament to the chef’s experience and human touch. Such interactions are a unique feature of high-end sushi restaurants that cannot be experienced at conveyor-belt sushi restaurants.

There are also significant differences in the toppings used and the depth of preparation. At conveyor belt sushi restaurants, cooking processes are streamlined to accommodate large volumes, and frozen or pre-processed ingredients are commonly used. Traditional Edomae-style techniques such as kobujime (kelp-wrapping), sujime (vinegar-marinating) are rarely seen, and the standard style involves placing ingredients on rice shaped by machines. This streamlining contributes to the appeal of enjoying sushi affordably and quickly.
In contrast, high-end sushi restaurants use fresh, natural ingredients sourced daily, with each ingredient prepared in the most suitable way. The sushi chefs carefully craft each piece to bring out the individual characteristics of the ingredients, and even the rice is meticulously prepared, with attention to the type of rice, vinegar, and temperature. The chefs adjust the size and firmness of each piece based on their judgment to achieve the perfect harmony between the ingredients and the rice.

Furthermore, there is a significant difference in the atmosphere of the restaurants themselves. At conveyor belt sushi restaurants, the layout prioritizes efficiency, with tables as the main seating arrangement. The interior design and furnishings are often cost-effective, creating a bright and casual atmosphere. In contrast, high-end sushi restaurants feature natural wood counters, carefully selected tableware, and soft lighting, with a consistent aesthetic throughout the space. Even the chairs, chopstick rests, and chopsticks are made from high-quality materials, all functioning as part of the stage setting for the art of sushi.

Even among high-end sushi restaurants, there is a wide range of styles. For example, some restaurants, like “Sukiyabashi Jiro,” serve only sushi, with no appetizers or side dishes, focusing solely on the sushi itself. Others offer a course that includes appetizers, grilled dishes, and simmered dishes before the sushi, allowing customers to enjoy the pairing with sake. Especially in the latter style, rare local sake and seasonal limited-edition sake from all over the country are available, and the entire course is presented as a story, taking into account the compatibility of the dishes with the sake.

On the other hand, conveyor belt sushi is basically designed as a place to enjoy sushi quickly and easily, with drinks centered around beer and standard sake. Appetizers and side dishes are not emphasized. In this way, even among high-end sushi restaurants, there are those that “compete solely on the quality of their sushi” In this way, conveyor belt sushi and high-end sushi restaurants have completely different philosophies and roles, from price, serving style, ingredients, and space to the relationship with the chefs. Conveyor belt sushi combines efficiency and fun, making sushi a more everyday part of Japanese cuisine. High-end sushi restaurants present sushi as an “art of cuisine,” blending technical skill and aesthetic sensibility to convey the depth of sushi and the essence of Japanese culture.

By understanding the unique appeal of each and choosing according to your purpose or mood, you can fully appreciate the multifaceted nature of sushi as a dish.

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Revision date: June 2, 2025

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What are “Ikejime” and “Nojime”?

How the fish is butchered also changes the taste. If the fish suffers and struggles, the body wears and may be damaged, circulating oxidized blood throughout the body, which makes it lose flavor. For fish of high value such as sea bream, flounder, yellowtail, rudderfish and tuna, a method called “ikejime” is used.

The taste of tuna is said to be determined based on the preparations after being caught. The tuna is caught with as little suffering as possible and the nerves are killed immediately for an instant death. Generally, blood is then drained perfectly, entrails and gills are removed, the tail cut off and then the fish is placed in ice-water to lower the body temperature.

The medulla oblongata and main artery of the fish are cut and a kitchen knife is inserted into the base of the tail to drain the blood. A thin metal rod is inserted into the backbone to paralyze the nerves and at the same time controls the putrefied materials that come out of the spinal cord.

This extends the time until rigor mortis sets in, making it easier to maintain freshness and simultaneously preventing blood from circulating in the body, which also prevents the fishy smell.

Freezing the fish to death in ice water is called “nojime”. This method is generally used for small fish such as sardines, horse mackerel and mackerel that are fished in large volume. Although the freshness of the fish deteriorates more quickly than in the case of “ikejime,” it can be done in large quantities without a lot of labor and maintains a certain level of freshness afterwards.

At fish markets, the term “kill” is not used for living fish, instead the word “shimeru” meaning to close or tighten. The term “dead fish” is also not used. Instead the term “nojime” is used for fish that died naturally en route to the market. This stems from the awe of precious life and turning that life into food.

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Revision date: January 13, 2023

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Judge a chef’s ability and quality of the shop by its Anago

A photo of Anago — The simmered anago is soft and tender, with a melt-in-your-mouth flavor.

Anago and Edomae Sushi

Sushi restaurants that advertise “Edomae style” on the sign somewhat fear customers who order Anago (Japanese conger) right off the bat. If the customer then eats as if they are really taking the time to taste the sushi, then any chef not fully confident in their skills will want to hide under the sushi counter.

Anago is a topping that really demonstrates a chef’s skills (or lack thereof). Edomae-style sushi chefs work on many toppings. Anago is a perfect example of these toppings.

In the morning, sushi chefs purchase anago that has undergone Ikejime. The anago is placed on a special cutting board, and a skewer is inserted into the pectoral fin to secure it firmly.

A knife is inserted from the back, following the spine, and the fish is cut open while holding it firmly with one hand, all the way to the tail. The internal organs and spine are removed, and the head is separated from the body. Finally, the flesh is scraped with a knife to remove any remaining impurities, completing the process. While it may seem like a simple task when described in words, it requires a high level of skill.

Before cooking, the anago is rubbed with salt to remove the slime. Rubbing causes moisture to be drawn out of the eel. This moisture contains the fishy odor of the eel. This process removes the characteristic muddy smell from the flesh. Additionally, as the moisture is removed, the flesh becomes more compact, making it less likely to fall apart even after prolonged simmering. However, the flesh does become slightly firmer due to the loss of moisture. Some sushi chefs rinse the eel with hot water and carefully remove the slime with a knife.

Since the fish is plain, the flavoring is also a subtle skill and not an easy task. Depending on the shop, the chef may make the sushi with the boiled fish, use Nitsume to bring out the flavor or lightly roast the fish before combining it with the rice. The chef’s ideas and abilities are apparent in the final dish. If the sushi is made from the freshly boiled fish, it should be soft and melt in your mouth…if the chef knows what they are doing! Lightly roasted Anago will have an aroma that fills your entire mouth.

The work this topping takes to serve is a chance for sushi shops to show off their specialties, but it is also a clear indicator of the quality of the shop. The level of the chef and quality of the sushi shop will be revealed as soon as you place Anago in your mouth.

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Revision date: June 11, 2025

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Kohada (Gizzard shad) flavor is refined by exquisite salt seasoning!

According to most sushi masters, salt is the defining factor in the taste of gizzard shad (kohada).

Before seasoning gizzard shad with vinegar, the process starts with salting the spread open shad. It is the length the fish is salted that makes or breaks the fish. The reason for salting the gizzard shad is not just for flavoring, but also to draw out the umami of the fish. Salting for too long results in a briny taste; too short and the umami won’t come to the fore. The timing must be perfect in order to achieve that emotional “umami” moment.

This timing can be compared to boiling eggs: 3 minutes gets you soft-boiled eggs but five minutes gets you hard-boiled eggs. With eggs you can follow this rule of thumb, but no such rule exists for the spotted shad. The conditions for the salting time differ depending on the temperature, humidity, size of the fish and the degree of fat.

For example, a more slender fish in the middle of summer may be salted for 30 minutes, but a fatty fish in the winter needs to be salted for four hours. Just a few minutes longer or shorter than the perfect salting time completely changes the taste of the final dish.

Skilled chefs adjust the time on a daily basis according to the weather and the quality of the fish. Shops that can provide precisely the same spotted shad taste every day of the year are truly the best of the best.

Related contents:
TYPES OF EDO-STYLE PREPARATIONS

Gizzard shad (Kohada)

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Revision date: May 29, 2017

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Salmon is not used as a topping in Edo-style sushi!

The Japanese were not in the habit of eating salmon raw. Salmon was not a traditional topping in Edo-style sushi. The reason for this is that the existence of parasites has been well-known since long ago and there was no way to prepare the salmon raw.

According to the Ministry of Health, Labour and Welfare, salmon must be frozen at -20℃ for at least 24 hours in order to completely kill all parasites. Salmon served at sushi restaurants must be stored frozen and then thawed before serving.

The type of salmon (sake) you find in Japan is Chum salmon. However, most of the salmon served raw at sushi restaurants is Atlantic salmon. This is a popular topping throughout the world due to the high-fat content and smooth texture achieved by sea farming in places like Norway and Chile. The fish are strictly managed from water quality to the effects on the environment, so there are very few issues with parasites and the salmon can be eaten raw. However, the fact remains that the fish are administered a number of chemicals due to concern of the spread of disease-causing germs in the farms.

Even when salmon roe and sea urchin first started to be used as toppings, most sushi chefs said that these didn’t count as Nigirizushi and refused to use them. However the favorable reputation of sea urchin sushi in Ginza won out, it started to be used by more chefs and eventually became one of the major dishes.

The fifth-generation sushi chef at one long-standing shop says, “If it’s what the customers want, then salmon may also be rolled as Nigirizushi in the near future.” It may even become part of the standard menu.

At a pre-Edo sushi shop that features Hokkaido toppings, they are actually serving ultra-high grade salmon such as Keiji* and Tokishirazu**.

*Keiji are young salmon with immature ovaries or testes. Only 1-2 Keiji are found in a normal catch of 10,000 salmon. Normal salmon fat content is 2-15% but the Keiji has a very high body fat percentage at 20-30%.

**Tokishirazu are salmon swimming upstream at the beginning of summer. They are the same chum salmon found in the fall, but since they aren’t caught during the spawning season, the fish don’t have eggs or milt, and instead have a high-fat content. The name “Tokishirazu” stems from the fact that these fish are caught out of season, in summer and the name means ”ignorant of time”

Why is it that sea urchin sushi can taste bitter?

What does sea urchin sushi taste like?!

Sea urchin has a creamy texture and rich flavor, with hints of natural sweetness and seaweed aroma. It leaves a lingering, rich umami flavor on the tongue. The acidity of the vinegared rice perfectly complements the sweetness of the uni. This is the general opinion of people who love sea urchin.

But some people say that “Sea urchin in a wooden box (called ‘hako-uni (箱ウニ)’ or ‘ori-uni (折ウニ)’ or ‘boxed sea urchin’) has a bitter medicine taste”.

The bitterness of sea urchin can be attributed to several factors, including changes in components due to decreased freshness, natural variations in taste depending on species or individual differences, the influence of the quality of seaweed used as feed on flavor, and the use of “potassium aluminum sulfate” (commonly known as alum) to enhance preservation and prevent deformation.

This alum treatment can also impart a distinctive bitterness, astringency, and metallic taste, making it a well-known cause of bitterness. As a result, many high-end sushi restaurants use sea urchin that is labeled as “additive-free” (no alum used).

If you’ve ever tried a sea urchin that tasted bitter*, this may be the reason.

*An “off flavor” that takes away from the primary good tastes.

What is saltwater sea urchin?

Sea urchin soaked in brine without using alum (called ‘ensui-uni (塩水ウニ)’ or ‘saltwater sea urchin’) is also commonly found. There is also a new technology that doesn’t use alum. In this method nitrogen water (water from which oxygen has been removed and then nitrogen dissolved) is used when sealing. The effect of replacing oxygen with nitrogen is inhibited oxidation, maintaining the freshness of the sea urchin.

Since it is sold soaked in saltwater with a salt concentration nearly identical to seawater, it has no bitterness or astringency, allowing you to enjoy the natural sweetness, umami, and seaweed aroma of the sea urchin, as well as its fluffy texture and juiciness. While it has a short shelf life, it is favored by sushi restaurants and high-end Japanese restaurants that prioritize quality. However, it is prone to losing its shape, so handling requires caution, and it is recommended to consume it as soon as possible after purchase.

Surprisingly, there are sushi restaurants established from over 100 years ago in Tokyo.

About 200 years ago (around 1810-1830), Yohei Hanaya opened up the oldest nigiri sushi restaurant in Japan. It is said that this was the beginning of edomaesushi. As expected, none of the restaurants remain to this day, no matter how popular they were in those days. However, if relating to those lasting more than a century, as many as 10 still exist in Tokyo. It is such a surprise and many respect that they’ve managed to survive, still keeping their business running now. We will introduce those old restaurants in the order of its establishment.

KUDANSHITA SUSHIMASA

First started as a stall in 1861 at Nihonbashi area, relocated to Kudanbashi and then opened the restaurant in 1923. The beauty of wooden architect managed to survive the war and it has a 100-year history. They carefully prepare sushi ingredients with appropriate amount of vinegar and salt. Take Kohada for instance, they adjust the amount of salt depending on the thickness of fish fillet, fat content, temperature and humidity of the air. Check the glossiness of the vinegared kohada fish, and decide the best timing to serve. Enjoy superb sushi prepared with the traditional recipe passed on for generations.

JANOMEZUSHI HONTEN　Established in 1865

BENTENMIYAKOZUSHI　Established in 1866

YAHATAZUSHI　Established in 1868

During the end of Edo period, many of samurai lords who had served for Tokugawa government lost their jobs. Many of them disguised themselves as dango rice dumpling seller. The first owner of Yahata-zushi was one of them, started the business as dango rice dumpling stall and then the second generation owner began serving sushi. The fourth and fifth chef now run the kitchen behind the counter. The fourth chef has a 62-year experience and he is the respected patriarch chef in Tokyo and serves traditional Edomae-style sushi with careful preparation. The fifth chef adheres to basic principle of sushi making while embarking on new-style. He uses sun-dried salt produced in the French Basque Country for well-matured akami red fish such as tuna, and sea urchin from Hokkaido. Other must-eat ingredients are, the highest quality tuna from long-time partner vendor at Tsukiji market and rare tuna caught at the sea near Miyakejima island and matured for good five days.

OTUNASUSHI　Established in 1875

YOSHINOSUSHI HONTEN

Opened in 1879, Yoshino sushi has served excellent Edomae-style sushi. Now the fifth-generation owner runs the restaurant. The second-generation owner first started using Toro, fatty tuna meat while most of the chef discarded it. That was because food freezing was not in widespread use at that time and fatty content of fish went bad quickly. Soon Toro was quickly raved by their regular customers as delicious treat. First it was called “abu” as it came from “abura” meaning fat in Japanese, but it didn’t sound as good as it tastes, so they changed it to “toro” meaning mild and tasty. They will feed you interesting stories to go along with sushi dish. One of them is that they had never considered Gunkan roll of ikura and uni sea urchin as sushi since Gunkan never requires hand rolling techniques as other hand roll sushi does. They use only salt and vinegar to make sushi rice not a slight use of sugar and mirin. And then they carefully prepare fish ingredients to go with vinegared rice. Enjoy delicious sushi dish however you like in a casual atmosphere.

JANOICHI HONTEN　Established in 1889

ASAKUSA SUSHISEI　Established in 1891

KIBUNZUSHI　Established in 1903

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Revision date: April 11, 2017

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