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Reevaluating the serious risk to health posed by farmed salmon!

Before continuing, please read the exclusive articles in major media and research papers.

The red tide (algal bloom) frequently occurs off the coast of Chile and it is resulting a large amount of salmon deaths. In 2015 27 million salmon died in a mass event, of which 25,000 tons were powdered and then fed to the healthy salmon (according to the UK’s Guardian reports).

Chilean fish farmers are using large quantities of antibiotics to control fish diseases. They use 500-700 times more antibiotics than Norway does. 80% of antibiotics imported into Chile are intended for the fish farming industry. Faced with the risk of bacteria resistant to antibiotics emerging, as highlighted by the World Health Organization (WHO), the Chilean National Fish Service is calling for a reduction in the use of antibiotics. (Extract from Le Monde diplomatique Japanese edition）

The bright color of salmon is something that you would never see a long time ago, but is now commonplace. It is likely due to the Canthaxanthin pigment mixed into their feed. Salmon is in fact a white fish. The salmon that is caught in Japan is called “Shirozake” or white salmon and its flesh is not a pink before it goes out to sea. Once it is out at sea, it swims around consuming small plankton and crustaceans such as shrimp and krill. Its body then takes on a pink color due to the intake of natural coloring of Astaxanthin. This Astaxanthin has antioxidant effects and it is noted for playing a part in relieving fatigue and preventing aging. However, the synthetic pigmentation that creates the salmon pink does not provide the same health benefits.

The US Food and Drug Administration (FDA) gave approval for genetically modified salmon on November 19th, 2015. This genetically modified salmon is called “AquAdvantage salmon.” It grows faster than regular salmon and its body length is almost double. There are groups opposing the sale of this salmon, including US citizen group Center for Food Safety, the Japanese Seikatsu Club, and the European parliament. There are still many unknowns regarding the safety of this type of fish for human consumption, and a number of issues are still being debated. The discussion has been featured in “Nature” magazine.

Endosulfan is a type of organochlorine compound, like Dichloro Diphenyl Trichloroethane, Dicofol, Heptachlor, Chlordane, Mirex, Pentachlorophenol, and is known to be extremely toxic, but the EU approved Endosulfan for use as feed in Norway’s salmon farming industry in 2013.

Researchers analyzed the risk-benefit ratio based on levels of contaminants like dioxins, PCBs and chlorinated pesticides versus omega-3 fatty acid levels. While farmed salmon is higher in omega-3s, it is also significantly higher in these toxins (about 10 times) which can produce birth defects, lower IQ, and cause cancer. They determined the following based on origin of the salmon: “consumers should not eat farmed fish from Scotland, Norway and eastern Canada more than three times a year; farmed fish from Maine, western Canada and Washington state no more than three to six times a year; and farmed fish from Chile no more than about six times a year. Wild chum salmon can be consumed safely as often as once a week, pink salmon, Sockeye and Coho about twice a month and Chinook just under once a month.” (Extract from The Journal of Nutrition)

There is a saying, where there’s smoke, there’s fire. It is unlikely that big media outlet and research organizations would join forces to circulate incorrect information. Furthermore, this is not a problem that only affects certain countries like Chile or Norway. It should be considered as a problem for the entire farmed salmon industry.

On the other side of the debate, there are articles such as the following. Norway’s NIFES (National Institute of Nutrition and Seafood Research) sampled 13,180 farmed fish (of which 90% were salmon) and monitored them for medicines, substances that are prohibited by law, and other pollutants, publishing their report on August 17th 2015. In their latest report, it concluded that Norwegian farmed fish were safe and that illegal and undesirable substances were not observed to exceed standards. Further, it seems that they have confirmed decrease in most of the pollutants analyzed in the investigation.

But the fact is that, according to these articles, while the chemicals did not exceed standard values, they were certainly found to be present in farmed salmon. The other extreme would be to say that eating natural un-farmed salmon will not expose you to the potential risks from these types of chemicals.

However, that’s not really practical. The global production of farmed salmon is 2.5 million tons a year, approximately three times the 800,000 tons of naturally fished salmon. No matter what way you slice it, the option of farmed salmon isn’t going away anytime soon.

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What is Red Snapper the same as “Tai” (Sea Bream)?

In the United States, Sea Bream is often called a Red Snapper. However, strictly speaking, this is not correct.

Biologically, Snapper is a generic term for all species in the snapper family (Lutjanidae). Over 100 different species of snapper inhabit tropical coastal waters. Red snapper is mainly fished in the Gulf of Mexico.

They are called American red snapper or Northern red snapper in supermarkets. The scientific name is Lutjanus campechanus.

And there is another species of fish called the Red Snapper. The Australasian snapper or silver seabream (Japanese name is Goushu-madai) is a species of porgie found in the coastal waters of Australia, Philippines, Indonesia, Taiwan, and New Zealand. It is a close relative of the Japanese Tai and similar in shape, but the body color of this species is golden pink, with a lighter reddish tinge than Tai, and the blue spots are lighter in color and somewhat larger. The flesh is softer than that of the Madai because it has passed the rigor mortis stage before being imported to Japan. It has a light flavor that can only be found in natural products. The black capillaries on the flesh are noticeable, which may bother some people. Its scientific name is Chrysophrys auratus (Forster, 1801).

So, what is the fish that Japanese sushi restaurants call “Tai”?

They say there are over 300 different species of fish with “Tai” in the name, making up 10% of Japan’s fish. When we say “Tai” in Japanese, we are referring to “madai” or red sea bream. Red sea-bream is categorized in the “madai” family (Sparidae).

Incidentally, relatives of the sea bream often served at sushi restaurants include red sea bream (madai), crimson sea bream (chidai) and yellowback sea bream (kidai). While “kinmedai” (Splendid alfonsino) and “amadai” (horsehead tilefish) have the name “tai/dai” in them, they are not part of the same family as “tai”. Splendid alfonsino is a type of deep-sea fish.

In American supermarkets, Porgy (Stenotomus chrysops) is sold, which has a beautiful cherry color and looks like Tai itself. However, the taste is different from that of Tai, being softer and lighter in flesh. Around New York and New Jersey, it is called Porgy, and in Massachusetts, it is called Scup. It is native to the Atlantic Ocean.

Red sea bream and red snapper look similar, but when served as sushi, their texture and flavors are entirely different. So if you come to Japan, please try and eat natural madai. There is no “zatsumi” (overpowering bitterness) and it has a slight sweetness to it. This is the taste of tai, known as the king of the white fish. Just for your own reference.

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What is Kakushiaji?

Kakushiaji refers to a technique where a single seasoning (For example, sugar, vinegar, soy sauce, salt, etc.) is added to a dish. The Kakushiaji contrasts with the finished dish’s flavor, and is added in an amount too small to notice when served. This produces a clear improvement in flavor.

Examples include adding a little salt to heighten sweetness, or adding a little vinegar to a simmered dish. Sometimes these combination of flavors can be quite surprising, like adding a touch of chocolate to a curry.

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Revision date: November 7, 2018

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What is Umami?

Umami describes the delicious taste of savory flavor essences. For many years, people held to the belief that humans can taste only four basic flavors (sweet, sour, salty, bitter) unitil a japanese chemist named Kikunae Ikeda discovered a fifth flavor (glutamic acid) in the early 20th century.

The main umami ingredients are glutamic acid in seaweed, inosinic acid in dried bonito and meats, succinic acid in shellfish, guanylic acid in shiitake mushroom.

Many ingredients contain a wide variety of umami essences. In combination, they create a synergistic effect which produces an even more potent savory flavor.

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Revision date: October 31, 2018

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What is the difference between “鮨,” “鮓” and “寿司” (all ready “Sushi”).

As far as I know, there are three ways “sushi” is written on sushi restaurant curtains in Japanese kanji characters: 鮨, 鮓 and 寿司.

Do you know the difference? Most Japanese people don’t know the answer to this question.

Broadly, in the Kanto area 鮨 is generally used while 鮓 is more common in Kansai. 寿司 is used commonly everywhere in Japan.

However, of the three, only 鮨 and 鮓 are seen in ancient Chinese literature. 鮨 was seen as a dictionary entry as early as the 5th to 3rd centuries B.C., and it’s origin is described as combining “fish” and “shiokara” (briny flavor) resulting in the term 鮨.

On the other hand, in A.D. 1st to 2nd century dictionaries, “鮓” appeared, and is explained to depict “a storage container for fish.” Toward the end of the second century 鮓 was used for the term “narezushi”.

But around the third century, the briny meaning of 鮨 and the term “narezushi*” written as 鮓 started to be used interchangeably. That is how the words were imported to Japan.

In Japan, the character “鮓” was often used in literature from the end of the Heian era to the end of the Edo era. Eventually the use of “鮨” was revived during the Meiji era (for unknown reasons). It was a natural transition that Kanto came to use “鮨” and Kansai came to use “鮓”.

Incidentally, the kanji “寿司” was created from the phonetics. Its use for celebratory occasions became commonplace throughout Japan.

*”Narezushi” is the primitive version of Japanese sushi. It means covering seafood with salt and then soaking in rice for a few years as a form of lactic acid fermentation, which brings out the acidity.

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Revision date: April 29, 2020

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The migrating route of Inshore Pacific bluefin tuna and fishing place!

An illustration of Kuro maguro main prodution area — This is the migration route of Kuro maguro (bluefin tuna).

Tuna caught in the coastal regions of the Japan Sea is notable as the best bluefin tuna in January. Iki, a small island in Kyushu area is one of the famous ports for tuna.

In February and March, the tuna auction market becomes slack due to rough weather. Just a few tunas from Nachikatsuura where is also the famous port for tuna are on the market.

In March and April, tunas become thin because their eggs need many nutrients.

In May, large tuna is seldom seen in the Tsukiji Fish Market. Even if there is, its body is really thin. “Kinkaimono” which means a shore-fish is generally considered as high-class tuna, but in this season, imported tuna is useful instead.

It is said that Pacific Bluefin tunas spawn around Japanese waters between Taiwan and Okinawa in April and May. And then, they go up to fertile, north sea along the eastern coast of Japan.

In June, “Chubo” which is young and small tuna is taken hugely off the coast of the Sea of Japan. The school of Chubo begin moving northward in this season.

In July and August, tunas can be seen occasionally but their bodies are still thin. Instead, Boston Tuna which is caught in the Atlantic Ocean and nicknamed “Jumbo” is on the market. Its fresh is softer than “Kinkaimono” and it doesn’t have medium-fatty part which “Kinkaimono” has.

In September, Boston Tunas are at their best with plenty of fat on them. The best season of Boston Tuna is limited and ends in October. But fortunately, Japanese tunas come into season.

The school of tunas split up into two groups, the one takes Pacific Ocean route and another takes the Japan Sea route and both of them move northward along the Japanese Islands. Some of them reach the Tsugaru Strait where and the season of Tuna begins from September to next January. Oma town and Toi town is famous nationwide for its catch of tuna from the Tsugaru Strait. The flavor of tuna in September is still weak but it becomes stronger in October. In November, feed of tunas such as Pacific saury or Japanese common squid with plenty of fat increase and flavor of tuna also gets stronger. In December, the peak season comes around.

A catch of tuna falls off in January and it enters the final season. The temperature of sea water gets cold and feed of tuna, squids decrease and the fishing season in this area ends.

Where should soy sauce be applied to the sushi?

The most delicious way to eat sushi at restaurants where the sushi chef applies Nikiri (soy sauce perfectly evaporated with sake) for you is just the way it was prepared. However, at restaurants where sauce is not applied for you, the sushi is eaten by dipping it in soy sauce. The soy sauce used for dipping is provided for you at the counter or table. Many restaurants use the same evaporation formula for the dipping soy sauce.

Soy sauce for dipping is put into a small dish for use, but don’t put in too much. It depends on the depth of the small dish, but the diameter of the circle of soy sauce after being poured should be approximately 25mm.

When dipping sushi into the soy sauce, turning it upside down (although it will be somewhat tilted) and dipping the topping seems to be the most common method. If you keep the topping on the bottom when you put the sushi in your mouth, the flavors of the soy sauce and the fish are in complete harmony and the delicious taste spreads through your mouth. There is also an opinion that turning the sushi upside down for dipping is unacceptable practice. There are also some with the opinion that whether to eat with your hands or chopsticks depends on the situation.

Make sure not to get any soy sauce on the Shari (vinegar rice). You don’t want to add unnecessary saltiness to the Shari, which has already been seasoned. It would be a terrible waste to cancel out the exquisite balance of the topping, wasabi and Shari with the saltiness of soy sauce.

What is Uwami and Shitami?

Large fish that are caught are always kept and transported on their side with their heads facing left from the port to the market and to the restaurant where they are served. The part of the fish facing down when in this position is called “Shitami” or the “bottom body” and the part facing up is called “Uwami” or the top body. The Uwami costs more than Shitami. This is because the Shitami takes on the weight of the Uwami, reducing the freshness and possibly causing cracks in the body (cracking occurs on the edges of the muscles).

This mostly applies to Pacific bluefin tuna (tuna that is consumed without any freezing after being caught). At any rate, since this fish costs hundreds of dollars per kilogram, a full-grown fish may be worth more than a luxury sports car. Therefore, from the time they make their catch, the fishermen work quickly, which affects all aspects of the quality. Most of all, this work affects the price. A Pacific bluefin is never placed directly on the deck of the ship. If a fish weighing 100 kg or more is set directly on the hard deck, its own weight would cause injury to its surface. Naturally, any damage or injury to the fish reduces the price. Instead, each fish is laid on a soft, spongy mat to protect its skin surface. Next, the blood is drained, the spinal cord nerves are destroyed and the fish is submerged in ice water. It might be easier to understand if you imagine handling a luxury vehicle, like a Ferrari, rather than a tuna fish.

Incidentally, the idea behind keeping the “Left side up (or prioritized), right side down,” is a fixed Japanese etiquette, passed down through China from the Asuka period. Perhaps the reason fish are also served for eating and photographed with the head on the left side is due to this influence as well. However, this is only a fixed practice within Japan.

At sushi restaurants, one of the many things the chef teaches their apprentice is to, “Start using purchase fish from ‘Shitami’.” Once a sushi topping is prepared, it may be served for several. It’s hard to imagine that the Shitami would start to go bad during these several days, but it is attention to these small details that make a master sushi chef.

Why is freshly-caught fish allowed to age?

The most delicious time to eat fish differs depending on if it is served as sashimi, as sushi, or boiled. Fresh does not necessarily mean delicious. For example, Japanese Amberjack should be used in sashimi 3-5 days after being caught, in sushi a week after being caught and it can be used in a stew or boiled once it turns black around the edges. This is because the inosine acid, which is responsible for the umami taste, increases after rigor mortis ends and understanding the timing of the peak in flavor is up to the skill of the sushi chef.

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Revision date: March 12, 2018

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Why don’t I notice the fishy smell in sushi restaurants?

Many overseas visitors who aren’t used to eating fish have an aversion to fishy smells. This is actually the smell of a substance called trimethylamine and is generated by the breakdown of the umami component called trimethylamine oxide found in large amounts in fish by bacterial growth. The smell also gets stronger with the generation of ammonia as more time passes.

Bacterial growth can be controlled with refrigeration so toppings at sushi restaurants are kept cold. Trimethylamine is an alkaline, so smells can be eliminated by washing with vinegar, which is acidic. It is also possible to kill bacteria on the surface of the fish by soaking it in vinegar, reducing the number of bacteria. Basically, sushi restaurants are constantly taking measures to prevent bacterial growth and avoid fishy smells.

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Revision date: February 19, 2018

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Is sushi eaten with your hands? Or should you use chopsticks?

Sushi was originally a food eaten with your hands. Even, for example, if you are in a prestigious sushi restaurant in Ginza, you can still eat with your hands. You can actually use your hands to eat the ginger too. Restaurants that prefer you to eat with your hands will provide an extra, smaller towel for cleaning your hands between sushi, along with the normal hand towel (Oshibori towel). Even then, feel free to use chopsticks if you prefer.

Anyway, using chopsticks for the first time can be challenging, but don’t worry – here is the ultimate guide to becoming an expert at picking up your favorite sushi without damaging it. You’ll learn how to use chopsticks like a pro.

Follow these simple steps to use chopsticks like an expert:

Hold the chopsticks by their thickest end.
Place the chopstick on the lower end of your hand in the gap between your thumb and index finger.
The chopstick on the top goes on the fingerprint of the thumb and index finger.
To pick each piece of sushi, move the upper stick with the help of your thumb, index, and middle fingers.

Follow the steps above and soon, you’ll be the one teaching your friends! Now you know how to pick up sushi with chopsticks!

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Revision date: September 14, 2023

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Why is sushi with tuna topping so expensive?

A purchase of raw tuna costs at least JPY 30,000 per kilogram. Furthermore, good tuna is judged not only by taste, but appearance is also highly regarded.

The surface is gradually oxidized by letting it sleep (mature) and the sushi chef makes sure that parts are cut of as they change color, when the timing is perfect for both the taste and appearance. In other words, skin is taken from the freshly purchased tuna, the meat of the fish darkened by blood (the blackened area that can’t be used as sushi toppings) is removed, the parts that have changed color are shaved off and then only the remaining, best parts used as toppings are left.

This is why the price is high.

Some notes on chopstick manners

There are manners in using chopsticks that tourists may be unaware of. We would like to introduce some of those here.

First of all, it is impolite to place chopsticks on your dish in the middle of a meal. Make sure to place them back on the chopstick stand when you aren’t using them.

It is also poor manners to stab food with chopsticks (Sashi-bashi) and or to use chopsticks to look through dishes. Please avoid breaking up the beautifully arranged dishes when you eat.

The improper use of chopsticks

1. Passing foods (Hiroi-bashi or Awase-bashi): Never use your chopsticks to take something from someone else’s chopsticks. This way of passing things relates to Japanese funerary customs (Kotsuage).

2. Drawing plates or bowls near you (Saguri-bashi): Don’t draw a plate or bowl toward you with chopsticks.

3. Touching foods unnecessarily (Utsuri-bashi): Don’t touch foods with chopsticks unnecessarily without eating them.

4. Scooping: Don’t scoop up food by using chopsticks like a spoon and bring them to your mouth.

5. Shoveling food into the mouth (Komi-bashi): Don’t put your lips on a plate or bowl and shovel food into your mouth with chopsticks.

6. Picking up plates or bowls while holding chopsticks (Nigiri-bashi): Don’t pick up a plate or bowl while holding chopsticks.

7. Pointing at someone (Sashi-bashi): Don’t point at someone with chopsticks.

8. Laying chopsticks across a plate or bowl: Don’t lay chopsticks across a plate or bowl.

9. They stuff their mouth full of food and push it in with chopsticks (Oshikomi-bashi).

10. Lick the chopstick tips (Neburi-bashi).

11. Hold it with chopsticks while dripping the cooking juices (Namida-bashi).

12. Eating the same food over and over again (Kasane-bashi).

Related contents: SUSHI RESTAURANT ETIQUETTE

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Revision date: March 1, 2024

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Where should I grab the sushi when eating with chopsticks?

Laying the chopsticks sideways as if scooping up the sushi distributes the strength and the sushi won’t break easily. If you grab it in the middle then there will be too much force on that part and it will break in two pieces. Make sure to eat this beautifully formed piece of sushi in one bite.

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Revision date: December 4, 2017

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Is there a certain order for eating sushi?

How to eat sushi properly

During the Edo period when Nigiri sushi originated, it was sold in food stalls. People chose the sushi topping they wanted and satisfied their hunger. There is no such thing as the order of eating. In the first place, there are no rules about how to eat food.

The order in which the food is eaten is at the discretion of the eater.

You can eat Nigiri sushi in any order you like. We dare say that the order of eating dessert first, then the main meat or fish dish, and finally the appetizers is not a good one. Something similar to this even exists in Nigiri sushi.

Recently, Nigiri sushi has become a mainstream dish served in the Omakase course, in which the sushi chef has thought of the best order to eat the sushi. In this case, the sushi chef has thought of the best order in which to eat the sushi. The eater is left to his/her own choice.

Since when do we care about the order of eating?

This is due to the internationalization of Nigiri sushi. Everyone is taught how to eat a dish for the first time. And if you don’t know much about sushi topping, it is only natural that you would want to know more about it.

Generally, start by eating fish with a lighter flavor like white fish and move onto fish with a heavier flavor such as Toro, Uni, Japanese conger (Anago), and then Egg (Tamagoyaki). Finishing with Seaweed rolls at the end is a typical way.

The following menu is an Omakase style at the Former 3 Michelin star restaurant in Ginza. Since Sayori is offered, one can imagine that the season is early spring. This menu is composed of sushi topping that changes as the seasons change.

Begin with white fish?

Marbled flounder (Makogarei)

Striped jack (Shima aji)

Golden cuttlefish (Sumi ika)

Akami

Chutoro

Otoro

Gizzard shad (Kohada)

Common orient clam (Nihamaguri)

Horse mackerel (Aji)

Kuruma prawn (Kuruma ebi)

Japanese halfbeak (Sayori)

Common octopus (Madako)

Mackerel (Saba)

Ark shell (Akagai)

Uni

Salmon roe (Ikura)

Japanese conger (Anago)

And Omelette (Tamagoyaki) comes last, just along the general order. Perhaps the way this owner serves might have become common.

To maximize each flavor of toppings, have some pickled ginger or hot tea between different types of sushi to cleanse your palate. You don’t have to stick to the specific order, though. It seems like having customers eat freely is the idea held in common by most sushi chefs. However, indeed, you won’t be able to taste the next flavor after eating something rather sweet. Japanese conger (Anago), Egg (Tamagoyaki), and Kanpyoumaki should be eaten at the end.

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Revision date: January 29, 2024

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