What is Brown trout sushi?

a photo of Brown trout
Brown trout is a popular target in controlled fishing areas.

What is Brown trout?

In Europe, the word “Trout” often refers to Brown trout. It has been transplanted to many parts of the world as an angling target fish.

Since the 1860s, it has been transplanted to all parts of the world and has become established in natural waters. It appears to have been transplanted to Japan in the 1930s via the U.S. mixed with Brook trout eggs, and natural reproduction has been confirmed in Lake Chuzenji, Lake Ashi, and the upper reaches of the Katsura River.

Body shape is similar to Rainbow trout, etc. The body color is grayish blue with relatively large black spots on the dorsal surface of the body and near the base of the dorsal fin, and whitish-orange spots below the lateral line. 1-5 years in freshwater, then become smolt and descend to the sea, spending 6 months to 5 years in the ocean. The descending type is also called Seatrout. Some spend their entire lives in freshwater areas such as rivers and lakes. It reaches a maximum length of 0.7 m.

What does Brown trout sushi taste like?

Brown trout is said to have less fat and a lighter flavor than rainbow trout, and when eaten as sashimi, it should be frozen completely before eating, since it is a freshwater fish, it is possible that parasites may be hidden in it. It also has a fishy odor unique to river fish, so it is necessary to quickly remove the blood. However, we have never heard of a sushi restaurant serving brown trout nigiri. Brown trout and Rainbow trout hybrids are sold as Shinshu-salmon (信州サーモン), and their market price is over 2,000 yen per kilogram. Shinshu-salmon nigiri is commonly eaten in Nagano and other places in Japan.

In Europe, where it originated, it is a high-grade fish that is delicious to eat. It is farmed mainly in France and Austria for eating purposes. However, compared to Rainbow trout, it grows more slowly and is more difficult to farm, so there are only a few companies that provide it. Hence, it is expensive. The main way to eat trout is to cook it. Incidentally, Schubert’s song “The Trout” was inspired by the brown trout.

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: February 16, 2023


Share this article

What is Beni toro?

a photo of Fresh fillet of Benizake
Fresh fillet of Benizake (Sockeye salmon)

Toro was originally used for bluefin tuna (and later for all tuna), but Beni toro was probably the first example of the term being applied to a fish other than tuna.

Around 1970, a major fishery company called Kyokuyo (極洋) gave the name to a sashimi product of fatty Benizake (sockeye salmon; Oncorhynchus nerka) caught in the North Sea, which had not yet entered the spawning migration stage.

It took many years from application to approval due to various problems, but Beni toro became a legitimately registered trademark in 1987. The registration number is 1991889.

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: February 13, 2023


Share this article

What is Biwa trout sushi?

a photo of Biwa masu
Biwa masu (Biwa trout) nigiri served at Kyogoku zushi.

What is Biwa trout?

Biwa trout is a species of fish native to Lake Biwa, but is also found in Lake Kizaki, Lake Chuzenji, Lake Ashi, and other lakes through transplantation. The Japanese name for Biwa trout is Biwa masu (琵琶鱒). As indicated by its scientific name, Oncorhynchus masou subsp., it is considered to be a subspecies of Satsukimasu (Red-spotted masu trout). It reaches up to 60 cm, and the spots on the body are pale orange and disappear with growth. The adult one has a silver colored body.

It has also been farmed in Japan for a long time. There is even a famous Biwa trout farm near Lake Biwa in Shiga Prefecture that has been in operation since 1878.

An interesting fact about Biwa trout is that it is a landlocked variety of Pacific Salmon while being anadromous as it moves between the freshwater lake Biwa and surrounding rivers according to the water temperature as part of its life cycle.

What does Biwa trout sushi taste like?

The natural Biwa trout season is from June to early September. At this time of year, it has no peculiar flavor and has large amounts of fat with refined sweetness. When you put it in your mouth, only the delicious flavor of the fat spreads out as if it were melting softly. The rich flavor of trout can also be fully enjoyed as a sushi topping.

Sushi restaurants in Shiga prefecture, such as Kyogoku-zushi, serve Biwa masu nigiri sushi during the summer months. Ordinary Ikura is red in color because salmon go down to the sea and feed on crabs and shrimps, taking in red pigment. Biwa masu, on the other hand, grows only in lakes, so it does not take in any pigment and its eggs remain golden. Kyogoku-zushi also offers this Golden Ikura sushi. Both are rarely seen at sushi restaurants in Tokyo.

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: February 7, 2023


Share this article

What is Longtail tuna (koshinaga maguro) sushi?

An illustration of longtail tuna
An illustration of longtail tuna (© 2023 – Fishing Spots)

What is Longtail tuna (Koshinaga maguro)?

Longtail tuna inhabits continental shell and ocean waters in warm temperate and tropical regions of the Ind-west pacific. The dark blue-backed fish is recognized by their short pectoral fins and slender body. Its tail is long compared to other tuna. It is also distinguished by the presence of elongated, colorless spots on the underside and belly, between the pectoral and anal fins. As the name suggests, it is characterized by a rather long tail from the tail fins to the tail.

It reaches a maximum length of 1.5 m and up to 32 kg in weight. It is caught by longline fishing in Southeast Asia and Australia.

The Japanese name is Koshinaga maguro (腰長鮪). It is caught in small numbers in Kagoshima, Nagasaki, and Okinawa prefectures, but its numbers are small and it is the least caught species of the tuna genus, so it is traded only in its place of origin and rarely appears on the market. In addition, juvenile tuna look similar to bluefin tuna, yellowfin tuna, and albacore. Therefore, they are sometimes confused in the market.

What does Longtail tuna (Koshinaga maguro) sushi taste like?

In northern Kyushu and Sanin regions where bonito are not caught, however, it is an autumn treat. Most of its flesh is red meat, and its taste is refreshing so it is eaten as sashimi. However its fat is not sweet and has little acidity, so it is not suitable for nigiri sushi. In Australia and Southeast Asia, it is eaten as steak or sauteed.

Its scientific name is Thunnus tonggol (Bleeker, 1851).

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: February 2, 2023


Share this article

What is Blackfin tuna (Taiseiyou maguro) sushi?

An illustration of Blackfin tuna
An illustration of Blackfin tuna (Image credit: Duane Raver Jr.)

What is Blackfin tuna (Taiseiyou maguro)?

Blackfin tuna is one of the smallest members of the species of Tuna belonging to the genus called Thunnus and family of Scombridae. The English name blackfin tuna comes from its black pectoral fins and other fins. It is known by various interesting names like Blackfinned Albacore, Bermuda and football due to its typical football like appearance.

The Japanese name is Taiseiyou maguro (大西洋鮪). There is also a species called Taiseiyou Kuro-maguro (Atlantic bluefin tuna), which is very confusing. It is not distributed in the Japanese market.

The range of distribution of these tuna is restricted as they can only be spotted in the West Atlantic Ocean, encompassing the Gulf of Mexico, southern Brazil and the Caribbean Sea. This is unique for a species of Tuna to have a limited range but it probably has something to do with the Blackfin Tuna’s preference to migrate to temperate waters above 20℃. It is especially common in the Gulf of Mexico, where it is a favorite target of sports fishermen.

It can be identified by a dark-blue to black stripe across its back usually with a golden hue under it and a silver belly. It is the smallest in the Tuna family reaching lengths of about 1 m and weight of 20 kg. It is at its peak during autumn, winter, and spring in Florida Keys. Only 0.4 tons per year of blackfin tuna is caught in the world.

What does Blackfin tuna (Taiseiyou maguro) sushi taste like?

Though it doesn’t quite measure up to world-class bluefin, yellowfin or bigeye tuna in food value, it is very good in its own right. The top preparation method with fresh blackfin is undoubtedly sushi or sashimi, as it yields an incredible flavor and texture when raw, but it also excels on the grill or is seared over high heat. It also makes a delectable tuna salad.

Its scientific name is Thunnus atlanticus (Lesson, 1831).

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: February 2, 2023


Share this article

What is Gasutoro?

 

a photo of Gastoro
Image credit: © Copyright National Research Institute of Far Seas Fisheries, Japan Fisheries Research and Education Agency

Gasutoro (ガストロ) is widely distributed throughout the temperate and subarctic regions of the Southern Hemisphere, but is not known to be found in the Northern Hemisphere. It is found in the open ocean around Australia and New Zealand, at depths of about 200 meters. It has the English name “Butterfly Tuna (Gasterochisma melampus Richardson, 1845)” because of its large, butterfly-like abdominal fins.

It is mostly caught as bycatch in longline fisheries that catch southern bluefin tuna. This is due to the overlap in habitat with southern bluefin tuna.

It is often thought to taste similar to tuna, a popular sashimi fish, perhaps due to the inclusion of maguro and tuna names in its name, such as “Uroko maguro” and “Butterfly tuna,” but it actually does not resemble tuna very much.

It has a refreshing flavor more like swordfish tuna. The best way to eat it raw is marinated with soy sauce, which takes about 15 minutes for the whole saku (fillet).

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: January 28, 2023


Share this article

What is Geso?

Geso is not the name of a fish or shellfish.

a photo of squid

Geso refers to the 10 arms/tentacles of a squid.

A photo of Geta
The appearance of Geta (wooden clogs)

The reason squid arms came to be called “Geso” is that the shoes that are removed before entering the indoors in Japan are referred to as “Gesoku”. The name comes from a time when restaurants used to hold onto their customers geta (wooden clogs) and the cloak would tie them with a string in 10-pair units.

a photo of geso nigiri

Geso can be lightly boiled or grilled. For large squid, a butcher knife is inserted at the tip of the arm to peel off the skin membrane, and then the tips of the arms are cut off so the sizes match. When Nitsume or other sauce is applied and it is made into Nigiri, it has an excellent springy texture and scent of the sea. It is also used as Tsumami when drinking alcohol. In my personal opinion, the Geso child of Sumiika is nice and soft and worlds above any others.

a photo of gesoThis is one of the sushi terms that even most of the general public in Japan knows well.

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: July 2, 2024


Share this article

List of sea urchin producers in Japan

In Japan, six types of sea urchins are caught: “Bafun uni”, “Ezobafun uni“, “Murasaki uni”, “Kitamurasaki uni”, “Aka uni”, and “Shirahige uni. At sushi restaurants, “Bafun uni” and “Ezobafun uni” are sometimes called “Aka uni (red sea urchin),” while “Murasaki uni” and “Kitamurasaki uni” are called “Shiro uni (white sea urchin). Generally, red sea urchins are considered more expensive than white sea urchins because red sea urchins are sweeter and last longer, but recently, due to the effects of sea desertification, the place of origin has become more important than the type of sea urchin.

The “Kitamurasaki uni” is distributed north of the Tohoku region and the “Murasaki uni” south of the Tohoku region, the “Ezobafun uni” north of the Tohoku region and the “Bafun uni” south of Matsushima Bay, respectively.

The “Kitamurasaki sea urchin” is distributed north of the Tohoku region and the “Murasaki sea urchin” south of the Tohoku region, the “Ezo-bafun uni” north of the Tohoku region and the “Bafun uni” south of Matsushima Bay, respectively.

“Ezobafun uni” and “Kitamurasaki uni” are caught on Rishiri Island and Rebun Island, “Bafun uni” and “Murasaki uni” on Shakotan Peninsula, “Bafun uni” on the four northern islands (Kunashiri Island, Etorofu Island, Shikotan Island and Chimai Islands) and Sakhalin Island, “Kitamurasaki uni” on Sanriku, Hakodate, Matsumae, Esashi and Okushiri Island, and others. Aka uni is caught in Yura, Karatsu, Hagi, Iki, and Amakusa. In Kagoshima and Okinawa, the word “sea urchin” refers to the “Shirahige uni”.

The price of that sea urchin has not stopped soaring. It is said that the price of sea urchin has doubled over the past few years. Combined with the weak yen, we hear that the Toyosu market is losing out to foreign sushi restaurants and other buyers. Increasing conflicts and rising sea temperatures are probably part of the reason for this. And foreigners visiting Japan are beginning to understand the deliciousness of sea urchin, so the number of foreigners who do not eat sea urchin is decreasing. The situation is such that the price of sea urchin is rising more and more.

We have made a list of sea urchin producers as far as we know. We honestly do not know how we should utilize this information, but we hope it will be useful.

Higashizawa Suisan (東沢水産)a photo of higashizawa uni
143-1 Wakumoto, Chonai-cho, Kamiiso gun, Hokkaido 〒049-1104
+81-11392-5-5237
Types:Kitamurasaki uni

Hadate Suisan (羽立水産)a photo of hadate uni
2-19-1 Sunahara, Mori-machi, Kayabe-gun, Hokkaido 〒049-2222
+81-1374-8-3355
Types:Kitamurasaki uni

Tachibana Suisan (橘水産 まるひろの生ウニ)a photo of tachibana unii
238-6 Aza-Osaki, Kaminokuni-cho, Hiyama-gun, Hokkaido 〒049-0603
+81-139-55-3555
Types:Kitamurasaki uni

Daisen Komamine Kaisan (ダイセン駒嶺海産)a photo of daisen uni
142-1, Aza Furugamatanihei, Oaza Hebaura, Kazamaura Village, Shimokita-gun, Aomori Prefecture 〒039-4503
+81-175-35-2628
Types:Kitamurasaki uni

Kaneyo Ouyo Suisan (カネヨ鴎洋水産)a photo of ouyou uni
〒087-0025北海道根室市西浜町9-40
0153-24-5188
Kaneyo Ouyo Suisan

Ichikawa Hokkai Suisan (イチカワ北海食品)a photo of ichikawa uni
2-14-6 Toyosato, Chitose-shi, Hokkaido 〒066-0022
+81-123-22-8014
Ichikawa Hokkai Suisan
Types:Ezo-bafun uni、Kitamurasaki uni

Marukuni Suisan (銀次郎 マルクニ水産)
a photo of hakouni
12-3 Mangoku, Ishinomaki City, Miyagi Prefecture 〒986-2115
+81-225-97-5011
Marukuni Suisan

Okumura Suisan (マルタツ 奥村水産)
a photo of itauni
13-1 Hoka, Nemuro City, Hokkaido 〒087-0037
+81-153-27-1309
Types:Ensui uni

Ogawa foods (丸雅 小川フーズ)
 a photo of itauni
1-778-8 Shinko, Ishikari City, Hokkaido 〒061-3241
+81-133-77-5208

Kimura Suisan (カネキ 木村水産)
a photo of hakouni
1-129 Shinkawa-higashi, Hamanaka-cho, Atsukishi-gun, Hokkaido 〒088-1527
+81-153-62-3211
Kimura Suisan
Types:Ezo-bafun uni

Akiyama Suisan (マルケイ 秋山水産)
a photo of hakouni
3-17, Wangetsu-cho, Atsukishi-cho, Atsukishi-gun, Hokkaido 〒088-1100
+81-153-52-3808

Takahashi Shoten (マルタカ髙橋商店)
a photo of hakouni
2-13-2 Kiyotaka-cho, Nemuro City, Hokkaido 〒087-0025
+81-153-27-1066
Takahashi Shoten
Types:Nemuro・Northern territories(Murasaki uni、Ezo-bafun uni)

Konishi Shoten (丸幸 小西商店)
a photo of itauni
12-6 Aza Showa-machi, Oaza-Shiraganicho, Hachinohe City, Aomori Prefecture 〒031-0822
+81-178-33-7632
Konishi Shoten

Ogawa shoten (小川商店)
a photo of ogawa uni
89-5 Aza-Irie, Toyako Town, Abuta-gun, Hokkaido 〒049-5603
+81-142-76-2323
Ogawa shoten

Types:Kitamurasaki uni、Bafun uni

Kawakatsu uni kakou (川勝うに加工)
a photo of akauni
1-21 Yura, Sumoto City, Hyogo Prefecture 〒656-2541
+81-90-3673-7307
Types:Murasaki uni、Aka uni

Hirakawa Suisan (マルキ 平川水産)
a photo of hako uni
484 Biwase, Hamanaka-cho, Atsukishi-gun, Hokkaido 〒088-1532
+81-153-62-3556
Hirakawa Suisan
種類:Farmed Bafun uni

Taisho Bussan (泰匠物産)
a photo of itauni
125-4 Hoka, Nemuro City, Hokkaido 〒087-0037
+81-9050-70-8334
Types:Ensui uni

Marukyo Akatsuki (マルキョウ あかつき水産)


123 Hanasaki Port, Nemuro City, Hokkaido 〒087-0032
+81-153-23-3453
Types:Northern territories

柊流海産 生ウニ
8-10-5 Nishihama-cho, Nemuro City, Hokkaido 〒087-0025
+81-153-22-2033
種類:Northern territories

Marukyo Suisan (丸恭水産)
1-3-6 Shiomi-cho, Tomakomai City, Hokkaido 〒053-0012
+81-144-36-6644
Marukyo Suisan

Marukawa Kawamura Suisan (マルカワ 川村水産)


13-3 Hoka, Nemuro City, Hokkaido 〒087-0037
+81-153-27-1300
Marukawa Kawamura Suisan

Kananese Setoshoten (株式会社かねせ 瀨戸商店)

A photo of Kanese uni
The appearance of Kanese uni

8-123 Nishihama-cho, Nemuro City, Hokkaido 〒087-0025
+81-153-22-3501
Kananese Setoshoten
Types:Ezo-bafun uni, Ensui uni

Sapporo Kaneshin Suisan (札幌カネシン水産)

A photo of Kaneshin suisan uni
The appearance of Kaneshin suisan sea urchin

5-3-9, Hachiken 1-jo Higashi 5-chome, Nishi-ku, Sapporo, Hokkaido 〒063-0861
+81-11-676-9531
Sapporo Kaneshin Suisan
Types:Ezo-bafun uni, Ensui uni

Murakami Shoten (村上商店)

A photo of Murakami shoten uni
The appearance of A photo of Murakami shoten uni

1-8-10 Nanaehama, Hokuto-shi, Hokkaido 〒049-0111
+81-138-48-8311
Murakami Shoten
Types:Ezo-bafun uni, Kitamurasakuni, Ensui uni

Maruei Masaki Suisan (マルエイ正木水産)
68 Hanasaki Port, Nemuro City, Hokkaido 〒087-0032
+81-153-25-8131
Types:Northern territories

Fukushi Suisan (福士水産)
28, Notsuka, Rishirifuji-machi, Rishiri-gun, Hokkaido 〒097-0101
+81-163-82-1161

Kyoeibukai (共栄部会)
Aza Aonae, Okushiri-cho, Okushiri-gun, Hokkaido 〒043-1521
+81-1397-3-2215

Hakodate Fisheries Cooperative Association (函館市漁協共同組合)
16-7 Irifune-cho, Hakodate, Hokkaido, Japan 〒040-0057
+81-138-22-4673

Basically, even if you contact us, we are not sure if you can deal with us directly. As far as we know, for example, you would have to buy from an Intermediate wholesaler at the Toyosu market. And the ones with images are the Ita-uni (basic means of distribution are two types: on a plate and in salt water) that you often see at sushi restaurants.

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: August 28, 2024


Share this article

What is used as a substitute for the expensive Mongou ika?

an image of mongou ikaNo people in the world love squid more than the Japanese. Squid ranks third in import volume behind shrimp and tuna. Squid is brought to Japan from the oceans all over the world. There are between 400 and 500 species of wild squid on Earth. Some, like the pygmy cuttlefish, are tinier than 3 millimeters while the giant squid is over 10 meters.

There are about 100 species of squid that live in the waters surrounding Japan. Surume ika (Japanese common squid) makes up the highest volume of domestic-caught squid. It is used as a Yari ika or Surume ika topping in eastern Japan, but Surume ika isn’t used very often in western Japan. At sushi restaurants, squid like Sumi ika (Golden cuttlefish), Aori ika (Bigfin reef squid), Kensaki ika (Swordtip squid) and Mongou ika (Ocellated cuttlefish) go for high prices, but they are all caught in smaller quantities and therefore only available to high-end sushi restaurants that can procure them fresh.

There are some conveyor belt sushi restaurants that list Mongou ika (モンゴウイカ又はカミナリイカ) on the menu, but actually serve European common cuttlefish. It is produced in the waters off the coast of West Africa. Even some sushi restaurants do this. This is actually still too pricey for conveyor belt sushi though. What is generally used at conveyor belt sushi is Flying squid, which goes for only 1/10 the price of the European common cuttlefish and reaches 60 cm in length. Jumbo flying squid is also often used. The Jumbo flying squid is more than twice as long as the Flying squid and exceeds 1 meter in length. The Jumbo flying squid is mainly imported from places on the other side of the world such as Chile and Mexico. The thickness of the meat is similar to Mongou ika. However, a big drawback is that the Jumbo flying squid lacks the sweetness peculiar to squid. Therefore, it is soaked in water that has been artificially sweetened. This alters the dried out sensation to a plump, moist sensation, making the customer believe it is Mongou ika.

The squid must have a certain thickness in order to masquerade as Mongou ika. Rhomboid squid, which has a torso length of 80 cm is also disguised as Mongou ika. Rhomboid squid is found in the warm waters of the world and is even caught in relatively high volume in Japan. Large squid have a low price cost, so it’s good for the shops to make a profit. Furthermore, the sweetness is brought out more when frozen first than by serving it fresh. That means it can be used as Mongou ika without any need for the artificial sweeteners used in Flying squid and Jumbo flying squid.

The fact is that there are many substitute products for Mongou ika. But even so, it doesn’t change the fact that using ingredients disguised as others is an unacceptable practice.

Types of  substitutes for the Mongou ika

European common cuttlefish: Sepia officinalis (Linnaeus, 1758)

European common cuttlefish (ヨーロッパコウイカ) is found from the Atlantic coast of France to the Mediterranean and west coast of Africa. It is often caught in the waters around Morocco. Its body length is around 30 cm. When it first arrived on the Japanese market, it was called Mongouika, hence the name.

The scientific name sepia means black pigment and officinalis means medicinal, indicating that this is a material for Chinese herbal medicine. At processing plants in Thailand and China, the fish is made into fillets for sashimi, and then vacuum-packed and sent to Japan.

Flying squid: Ommastrephes bartramii (Lesueur, 1821)

Flying squid (アカイカ) is distributed in the North Pacific, South Pacific, and Atlantic Oceans. Its body length exceeds 40 cm, and it can weigh more than 4 kg. It is similar in appearance to the Surumeika, but has a darker, blackish back. It is used as a substitute for Surumeika for processing such as delicacies.

Jumbo flying squid: Dosidicus gigas (Orbigny, 1835)

Jumbo flying squid (アメリカオオアカイカ) is found only off the Pacific coast of the United States, Chile and Peru in South America. They are over 80 cm in length, weigh around 10 kg, and have as many as 100 to 200 suckers. In Peru, they are called Pota. Japanese fishing vessels used to catch flying squid mainly in the North Pacific, but their catch has drastically decreased due to the ban on drift net fishing.

Japanese vessels have switched to fishing for Jumbo flying squid, a member of the flying squid family, in the waters off Peru and other areas. Fishing for Jumbo flying squid in Peruvian waters continues from spring to fall.

Since the drifting net fishing of flying squid has been banned, it is the most promising resource as a raw material for processing. However, the larger ones store ammonia in their muscles, so de-ammonia treatment is required when processing them.

Rhomboid squid: Thysanoteuthis rhombus Troschel, 1857

Rhomboid squid (ソデイカ) is widely distributed in the warm waters of the Pacific and Atlantic Oceans. The body length is 70 cm. Its fins are diamond-shaped and the same length as its body. Because they do not form large schools and live scattered, they have been a difficult resource to exploit.

After a new fishing method was developed in the Tajima region of Hyogo Prefecture in the 1960s, the fishery began in earnest. Because of its reasonable price, it is often used in restaurants such as conveyor belt sushi restaurants. Also called Diamond squid or Diamondback squid.

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: March 24, 2023


Share this article

What is used as a substitute for Madako (Octopus)?

Among the many sushi toppings, Pacific bluefin tuna, and actually the Madai (Red sea bream) as well, are toppings that are difficult for an amateur to tell whether it is farmed or wild. However, there is no need to worry about that when it comes to Tako (Octopus). There are no octopus farms to be found in the world, so it is a 100% wild topping.

In Japan, domestic production isn’t enough to satisfy the appetite of Japanese who like Tako, so the majority relies on imports. Imports from Africa account for 80% and the remainder is imported from China, Southeast Asia, Mexico, Spain and other places in the world.

Most of the African imports are produced by nations on the northwestern coast, with the highest number coming from Mauritania. Until 2003 the highest volume came from Morocco for many years. However, due to continued mass catches to sell to Japan, Tako numbers dropped drastically, leading to the Moroccan government panicking and outlawing fishing. For some reason, Japanese people have grown to love Tako and now consume nearly half of the Tako caught throughout the world.

There are over 200 types of Tako in the world with approximately 60 types inhabiting the seas near Japan. Among these, the Japanese mainly only eat Madako, Mizudako and Iidako. Even among these, Madako makes up at least 80% of consumption.

Most of the Tako found at conveyor belt sushi is African Madako (Madako from Africa). African produced Tako is boiled on-site before being imported frozen. The cost is 20 cents or less per topping.

Amateurs can’t tell the difference between domestic Tako or African imports. However, there is one aspect that even an amateur can use to distinguish between the two. There is one condition for this to work, and that is that at least one of the suckers is in-tact. The suckers are scraped off for most toppings, but in cases where they are sliced by the restaurant, there are often suckers remaining. If the sucker is pure white, it is almost definitely from Africa. Meanwhile, domestic Tako suckers maintain a faint red color in the suckers, even when boiled. The reason the suckers turn white seems to be an effect of the food preservatives added during processing, but this has not been confirmed.

There happens to be a substitute for Madako as well.

One of these is the Iwadako from Vietnam, which grows as large as the height of an adult human. It is imported in frozen slices that can be used as raw Tako as soon as it thaws. The cost of this topping is 20 cents or less per piece. This ends up disguised as Hokkaido Tako.

There are also domestic substitutes. Yanagidako (Chestnut octopus) is mainly caught in the Pacific Ocean, from Chiba prefecture northward. The flavor is lighter than Madako, but it is also softer than Madako, so some people actually consider it to be better than Madako. If it is boiled and made into sushi, an amateur can’t distinguish between it and Madako. The legs are thin so they just need to be cut at an extreme angle in order to make the topping appear bigger. The cost of this topping is 15 cents or less per piece. It is also used as Mizudako because it is watery when eaten raw.

As you can see, there are also many substitute toppings for Madako.

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: December 21, 2021


Share this article

What is Toro Katsuo (Torogatsuo)?

Toro is an absolute at sushi restaurants and it’s only natural to aspire to such a position. That’s why there are so many sushi dish names that start with “Toro”. The most laissez-faire of these is Toro salmon. In this case the definition of Toro is ignored in an attempt to promote sales. Just as bad is Toro katsuo (pronounced “Toro-gatsuo” in Japanese).

Katsuo is born in the warm southern seas. When it reaches about two years old it migrates north in pursuit of Iwashi and other small fish. There are two routes taken by the Katsuo that come to the seas around Japan. One of the routes rides the Kuroshio Current (a warm current) from around the Philippines, passing by Taiwan and the Ryukyus Islands, arriving in southern Kyushu. From there the Katsuo rarely heads toward the Sea of Japan and instead the majority moves northward on the Pacific Ocean side. The Katsuo migration schedule may shift depending on the temperature of the seawater and how the schools of Iwashi and Aji (which the Katsuo feeds on) are migrating that year. The first group appears around Ishigaki Island about January, then in the seas off the shores of Kyushu and Shikoku between February and March. It then moves to the seas off of the Izu and Boso peninsulas between April and June. It reaches the open seas off the southern coast of Sanriku and Hokkaido between July and September.

Another route follows the Ogasawara ocean current from below the equator in the seas off the shore of Papua New Guinea and the seas around Micronesia to the Ogasawara Islands, along the Seven Islands of Izu and approaching the open seas off the Boso Peninsula. The route then goes northward to join with the routes mentioned above.

It’s the Modori-gatsuo that begins reverse migration toward the south at the beginning of autumn when the water temperatures start to drop. Katsuo has a strong appetite before returning south in preparation for the long trip. Unlike the light-flavored Hatsu-gatsuo, the Modori-gatsuo has plenty of fat and its body fattens up quite a bit. The main fishing locations for Modori-gatsuo are in the northern Pacific, such as the waters off the shore of Sanriku. This is the season when it is truly worthy of the name Toro katsuo when served raw, and nothing else should be called by the same name.

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: December 1, 2021


Share this article

What is Meki? Substitute for Kuruma ebi?

Japan leads the world in shrimp consumption by far. Most of the shrimp is imported, but it is a little known fact that shrimp is called “Meki” among importers and sushi restaurants in Japan. It is said to be a remnant from a time when much of the imported shrimp came from Mexico (pronounced “Mekishiko” in Japanese).

Shrimp can be caught within 45 degrees north or south of the equator. The caught shrimp is quick-frozen on site and then sent to Japan. Mexico was early in advanced refrigeration technology so when it became impossible to catch shrimp in the seas around Japan in the 1970s, a large volume of shrimp was already being imported from Mexico. It was around that time that importers shortened the phrase “Shrimp imported from Mexico” to “Meki”.

After that the major source of shrimp imports switched to Taiwan, which started shrimp aquaculture, and it is now also imported from Thailand, Indonesia and China. The name “Meki” stuck in the industry, despite the fact that shrimp is now mainly imported from other places in Asia.

Imported shrimp is categorized by body color tones, either brown, pink or white. The color is combined with the place of origin or country name and that is what each type of fish is called at the distribution stage. For example, they may be called Mexico brown or Guiana pink.

Well-known brown-toned shrimp include Ushi ebi (Black tiger shrimp) and Mexico brown (Yellowleg shrimp). Pink-toned types include Guiana pink (Pink spotted shrimp) and Nigeria pink ebi (Southern pink shrimp). White-toned shrimp include Taisho ebi (Fleshly prawn),  Banana ebi (Banana Prawn) , Eedeavour ebi (Eedeavour prawn) and Vannamei ebi (Whiteleg shrimp). There are many sushi restaurants that use pink and brown-toned sushi that turn into a nice red color when boiled. While the meat of white-toned shrimp is soft, it turns a whitish color when boiled and doesn’t look very appetizing. However, due to the splendid, large tail, it is perfect for tempura or fried prawns.

Next, We will touch on the characteristics of shrimp that is typically imported to Japan. All these types are actually related to the Kuruma prawn, which is representative of premium shrimp and a familiar ingredient of sushi. In other words, these imports are alternatives to make up for the shrimp consumption in Japan that can’t be covered by the Kuruma prawn. Normally the head is removed, it is frozen, packed in large lots, and then embarks on the distribution channel in Japan.

There are about 27 species of kuruma prawns (Penaeus japonicus Spence Bate, 1888). The following is a list.

Crystal shrimp: Farfantepenaeus brevirostris (Kingsley, 1878)

Witch Shrimp: Farfantepenaeus Burukovsky, 1972

Northern pink shrimp: Farfantepenaeus duorarum (Burkenroad, 1939)

Indian white prawn (Shonanebi): Fenneropenaeus indicus (H.Milne Edwards, 1837)

Caramote Prawn: Penaeus kerathurus (Forskål, 1775)

Western king prawn (Futomizoebi): Penaeus latisulcatus Kishinouye, 1896

Redspot King Prawn: Penaeus longistylus Kubo, 1943

Aloha Prawn (Terao-kurumaebi): Penaeus marginatus J.W.Randall, 1840

Western White Shrimp (Tenjiku-kurumaebi): Penaeus occidentalis Streets, 1871

San Paulo Shrimp: Penaeus (Melicertus) paulensis Pérez Farfante, 1967

Redtail Prawn (Akaoebi): Penaeus penicillatus Alcock, 1905

Southern White Shrimp: Penaeus schmitti Burkenroad, 1936

Green Tiger Prawn (Kumaebi): Penaeus semisulcatus De Haan, 1844

Northern White shrimp: Penaeus setiferus (Linnaeus, 1767)

-: Penaeus silasi Muthu & Motoh, 1979

Blue Shrimp: Penaeus stylirostris Stimpson, 1874

Southern Brown Shrimp: Penaeus subtilis Pérez Farfante, 1967

The following is a list of those commonly used in sushi restaurants and Japanese restaurants in Japan.

Guiana pink (Redspotted shrimp, Spotted pink shrimp /Farfantepenaeus brasiliensis (Latreille, 1817))

For more information, go here.

Taisho ebi (Fleshly prawn /Fenneropenaeus chinensis (Osbeck, 1765))

It is found from the Indian Ocean to the Pacific Ocean, the Malay Archipelago and Australia. The species is of considerable commercial importance in the Yellow Sea, East China Sea and Korean Bight, where it is trawled. It is sold in Korea, China, Japan and Hong Kong. This is a large shrimp that reaches up to 25 cm in body length. The appearance is similar to the Kuruma ebi, but without any special pattern. The edge of the abdomen is a dark brown color. There are 28 known species related to the Kuruma ebi. In the Toyosu market, those with a striped pattern are Kuruma ebi, and those without are Taisho ebi. In Japanese it’s been dubbed “Korai ebi” is due to the fact that it is often caught in the waters off the west coast of the Korean peninsula. The soft meat has a sweetness that makes this shrimp delicious. The number of wild Taisho ebi has decreased drastically in recent years. The coloring is lighter than Kuruma prawn and Black tiger shrimp, but darker than other white-toned shrimp. This type has a long history compared to other imported frozen shrimp and such high volumes were imported from China that it was called Chinese Taisho. It accounted for the majority of the market share until farmed Black tiger shrimp started to appear on the market.

Banana ebi (Banana Prawn /Penaeus merguiensis De Man, 1888)

It found around the northern coast of Australia from the New South Wales-Queensland border to Shark Bay in Western Australia, it is mainly caught by trawlers between Exemouth Gulf, Western Australia and Brisbane, with the bulk of the catch coming from the Gulf of Carpentaria. It weighs between 18 to 30 g per shrimp and is colored like a banana. The meat is soft and has a sweetness. Sometimes it is also sold as Taisho ebi. The body is thinner and slenderer than the Black tiger shrimp. It is available year round with peak supply in April.

Mexico brown (Yellowleg shrimp, Brown shrimp /Farfantepenaeus californiensis (Holmes, 1900))

For more information, go here.

Vannamei ebi (Whiteleg shrimp, Pacific white shrimp/Litopenaeus vannamei (Boone, 1931))

For more information, go here.

Ushi ebi (Black tiger shrimp, Giant tiger prawn/Penaeus monodon Fabricius, 1798)

For more information, go here.

Australia tiger (Brown tiger prawn /Penaeus esculentus Haswell, 1879)

The Australian tiger (Brown tiger prawn) is endemic to Australia and is found at depths of 15~20 meters along the coast except in the southern part of the country. Its main locality is the Gulf of Carpentaria on the northern coast of Australia. It reaches 25 cm in length but is generally 15~20 cm long.

Because of its beautiful red legs and reddish-brown stripes, this shrimp is mainly imported to Japan with its head on. In addition to its shape and size reminiscent of Kuruma ebi, it is a high-end variety that is not so tough, sweet, and has a good taste and coloration and is used in grilled dishes and tempura.

Nigeria pink ebi (Southern pink shrimp, Candied shrimp/Farfantepenaeus notialis (Pérez Farfante, 1967))

Nigeria pink ebi (Southern pink shrimp) is found from Mauritania to Angola at depths of 20~100m. It is also found in the western Atlantic Ocean from the Caribbean coast to southern Brazil.

It inhabits bottom mud or sandy mud, and sandy patches among rocks in marine environments. Juveniles are found in estuarine environments. Also inhabits lagoons. It is often used for sushi because of the soft meat, good flavor, and nice coloring. This is one of the highest grades of imported shrimp.

Mexico ebi (Northern brown shrimp, Brown shrimp /Farfantepenaeus aztecus (Ives, 1891))

Mexico ebi (Northern white shrimp) is distributed from the Gulf of Mexico to depths of up to 30 meters along the eastern coast of North America. Juvenile shrimp grows in estuaries. It is the most important species in the Gulf of Mexico, with an average annual catch of nearly 30,000 tons. On the other hand, Southern white shrimp is distributed in shallow waters from the Caribbean Sea to southern Brazil. It is almost indistinguishable from this species in appearance, but the male and female reproductive organs differ in shape.

Maximum standard length: 22 cm. It lives in bottom mud or peat, often with sand, clay, or broken shells. Adults inhabit the marine environment. Juveniles inhabit the estuarine and marine environments. There are 13 types of brown-toned Kuruma prawn in the world and the names get confusing.

Also called Golden Shrimp, Red Shrimp, Redtail Shrimp.

King ebi (Eastern king prawn /Penaeus plebejus Hess, 1865)

Adults are found in marine environments while juveniles are found in estuarine environments. It is found over sandy bottoms at depths of 2-350 m or deeper.

Finally, the shrimp introduced in this section is consumed not only in Japan but all over the world. Judging by the images on social media, takeout sushi and the frozen shrimp sold at Costco are made from one of the types of shrimp described here. If you’re going to learn about sushi, it’s important to learn the types of shrimp used in sushi.

India ebi (Indian prawn/Madagascar white prawn/Fenneropenaeus indicus (H.Milne Edwards, 1837))

India ebi (Indian prawn) is widely distributed from the Philippines through Southeast Asia to the western Indian Ocean. It is especially important in the waters from the Indian coast to the western Indian Ocean.

It is a White species of Kuruma ebi and is similar in appearance to the Banana Prawn. Once the head is removed, it is difficult to distinguish between the two species. In Southeast Asian markets, both species are sold together.

Those distributed in East African waters have brownish bodies and reddish legs. It has a rich flavor and aroma and is very tasty. It is suitable for frying and tempura.

Also called Indian white prawn, Tugela prawn , White prawn.

Endeavour ebi (Endeavour prawn/ Metapenaeus endeavouri (Schmitt, 1926))

Endeavour ebi (Endeavour prawn) are abundant in all waters except the southern part of Australia, but can also be caught in Philippine waters. It is found at depths of 20 to 45 meters. It is said to be caught together with shiba shrimp in some waters, but unlike shiba shrimp, it does not enter brackish water.

It is about 15 cm long and weighs about 17 grams. The entire body is covered with fine hair. Its scientific name is derived from the name of a research vessel, the Endeavour, which surveyed the eastern coast of Australia.

Also called Brown prawn, Endeavour shrimp.

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: June 15, 2024


Share this article

What is Sekisaba?

Sekisaba (関サバ) and Sekiaji (関アジ) are ‘designer’ fish known for their high prices.

Of them, Sekisaba is a premium fish that can go for as high as US $50 per fish. So, what kind of fish is Sekisaba and what’s the difference between it and normal Saba (Mackerel)?

Sekisaba is a Saba caught in the Hoyo Strait with a fishing pole by a union member of the Saganoseki branch of the Oita National Federation of Fisheries Cooperative (JF Oita). In other words, Sekisaba is not a type of Saba, but a premium fish created by differentiating the fishing method.

Sekisaba started to become known all over Japan between the late 1980s and early 1990s. Until then, Sekisaba was only known as a commonplace fish that was caught incidentally with Aji and went for US $2 per fish.

However, the Saganoseki branch of JF Oita applied for the first trademark ever in the industry and then grew the brand through methods such as tagging each individual fish by hand. This resulted in recognition of its taste as “Saba that can be enjoyed even as sashimi” (while Saba is generally a fish that loses its freshness easily and not eaten raw), catapulting it to a national constituency  After that, the thorough quality management and branding paid off and the price jumped to 10 times that of normal Saba.

The first difference between Sekisaba and normal Saba is that Sekisaba is caught carefully, one at a time. The use of ground bait is also banned so that the Sekisaba won’t eat anything but the natural diet (avoiding odor). Each fisher is only allowed to use fishing lures they make from fish skin or ragworms. Fish caught in this way are let out into a live holding tank on the ship and brought to the fishing port alive. After arriving at the port, the tank on the ship is checked, the fish size is looked at from the water surface and the approximate weight is measured. This method is called “Tsurugai”. This is because when the fish is placed on a scale, it struggles violently and can injure itself. The fish are allowed to calm down in the tank (called Ikekoshi) for a day at the fishing port. At the time of shipping, Ikejime is performed, in which a knife is put into gill parts, the spinal cord is cut, and then it is submerged into saltwater and the blood is let out. After that a processing method called Shinkeijime is performed in which a wire is inserted into the spinal cord to put the fish in a state of asphyxiation. Therefore, there is little damage to the fish, maintaining the freshness. When it is transported to the place of consumption, the temperature is kept at 5°C (41°F). This is because the fish does not lose its crunchiness compared to when it is cooled to 0°C. Even this is not easy to imitate.

The Hoyo Strait where Sekisaba is caught is rich in plankton, which the Sekisaba feeds on, and the flow of the tide is fast. The reason Sekisaba meat firms well and is fatty year-round is thanks to the good environment of the sea it is raised in.

If you come across a Sekisaba that so much work has been put into, try it as sashimi, not Nigiri sushi. This is because Saba, which has a peculiarity to it, is unpopular among some people. However, Sekisaba doesn’t have this off-taste and doesn’t taste like Mackerel, so even people who don’t care for fish should be able to find it tasty.

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: August 21, 2023


Share this article

What is Ishigakigai sushi?

Ishigakigai is a shellfish found from Kashimanada northward, Hokkaido, from the Kuril Islands to the Aleutian Islands and even on the west coast of North America. It lives off of plankton in the shallow sandy mud bottoms of the sea at depths of about 50 meters.

Aquaculture in Hirota Bay, Iwate Prefecture, has been successful and it started to appear at the Tsukiji Fish Market starting in about 2008, distributed as Ishigakigai. According to brokers, someone in the business at Tsukiji Fish Market misheard “Ishikage” as “Ishigaki” and the name stuck in the market. While Torigai meat looks black, Ishigakigai looks whiter, so it is also called “Shirotorigai”. The official name is “Ezoishikagegai”.

It starts to become common at the market when the Japanese rainy season ends, at the beginning of summer every year, which is around the end of the Torigai season. It then disappears from the market at the end of summer. A number of sushi restaurants start using it as a substitute for Torigai all at the same time, so Ishigakigai nigiri sushi suddenly started appearing on menus. Frankly, it is somewhat conservative as a nigiri topping but is known for the crunchy texture when biting into it. It also has strong sweetness and umami, which goes exquisitely with Shari. The sushi chef slaps the meat in his hand directly before serving to stiffen it–a way to increase the crunchy texture characteristic of shellfish. Naturally this texture is evidence of its freshness.

As the season of availability is short and the production sites are limited, Ishigakigai often fetches a high price. Those up for sale at the Toyosu Market go for $2 to $4 each. Wild-caught Ishigakigai is rarely found on the market, but when they are, the price is double that of the farmed version.

A relative of the Torigai, the Ishigakigai is rich in amino acids such as taurine, glycine and arginine. It is also resilient and can live for days, even outside its shell.

Related contents: Ezoishikagegai

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: October 5, 2021


Share this article

There are strangely two types of Ama ebi

It goes without saying, that each type of fish has its very own scientific name. However, in places like the Toyosu Fish Market, there are seafoods that end up sharing a name.

The official Japanese name of ama ebi (sweet shrimp) is “Hokkoku Akaebi” (scientific name: Pandaluseous Makarov).

In Japan, ama ebi lives naturally along the Sea of Japan coast and the coasts of Hokkaido, and the ama ebi sold at Toyosu market is caught from Toyama prefecture and northward to Hokkaido and southward. When made into nigiri sushi, it is harmonious with the acidity of the vinegared rice and the thick sweetness is irresistible. It really lives up to its “sweet” name.

However, what dominates the Toyosu Market is frozen shrimp of the same pandalidae family, called “Honhokkoku Akaebi” (scientific name: pandalus borealis kroyer) from Iceland and Greenland.

This is distributed as “Ama ebi” at the market, but strictly speaking it is a different type of shrimp. As far as appearance goes, it is impossible to tell the difference and they say that even the flavor is the same.

The majority of ama ebi used at conveyor belt sushi is produced in Greenland and imported to Japan through China. The reason for this import circumvention is that the processing to turn the shrimp into ready-made sushi toppings is done using inexpensive labor in China. The frozen ama ebi is thawed in China, processed (head, shell, etc., are removed) and then frozen again. Of course, this process diminishes the freshness of the fish. Preservatives are used to help prevent this. For example, pigment fixing agents are used in order to reduce discoloration from fading. Furthermore, acidity regulators and antioxidants are used to prevent changes in the quality and color of the meat. Ama ebi is stored in packs of 50, imported en masse to Japan, and can be used for sushi or sashimi immediately upon thawing.

As this ama ebi caught in the North Atlantic Ocean is considerably cheaper than domestic ama ebi, the reality is that conveyor belt sushi wouldn’t survive in Japan without these imports.

Related contents: Sweet shrimp (Amaebi)

[sc_apply url=”https://sushiuniversity.jp/apply/”]


We hope this information will be helpful.

Revision date: September 1, 2021


Share this article

Copy Protected by Chetan's WP-Copyprotect.