In academic terms, “fermentation” is a reaction that uses no oxygen to break down carbohydrates to obtain energy. On the other hand, the reaction that uses oxygen to break down organic matter to obtain energy is called “respiration”.
In more familiar terms, microorganisms such as lactic acid bacteria, koji-mold, and yeast break down organic compounds such as carbohydrates and proteins to produce a variety of by-products to obtain energy in their own life activities. Among these, “fermentation” is a phenomenon in which beneficial substances are produced for humans, while “putrefaction” is a phenomenon in which harmful substances are produced for humans. Food spoilage can be detected by the five senses, such as smell, appearance, and taste.
What is the difference between fermentation and maturing?
While “fermentation” and “putrefaction” are caused by microorganisms, “maturing” is a process in which the food itself is transformed by enzymes and other substances to produce something beneficial to humans. Or, “maturing” is the process of improving the flavor and quality of food by allowing it to rest under controlled temperature and humidity after fermentation is complete. Maturing is said to be beneficial to humans because it changes the texture and taste of the fish, making it tastier.
In case you are wondering, “enzyme” is mainly composed of protein, which promotes chemical reactions such as digestion, absorption, and metabolism that are necessary for all living things, including humans, animals, and plants, to survive. It is said that there are approximately 5,000 enzymes in our body, but each enzyme is a specialist that performs only one function and is largely divided into “Digestive enzymes” and “Metabolic enzymes.
Blackfin Seabass (Hirasuzuki) prefer warmer waters and are distributed south of the Boso Peninsula on the Pacific Ocean side, and south of Hokuriku on the Sea of Japan side, as well as in the southern part of the Korean Peninsula. Juveniles and young fish may be found near estuaries that connect to the open ocean, but as they mature, they move to areas of higher salinity and are not found in the brackish waters near estuaries.
It is very similar to the Japanese sea bass (Suzuki) only in the same genus, but is taller and more strongly laterally flattened than the Japanese sea bass. A large Blackfin Seabass exceeds 1 meter. The scientific name is Lateolabrax latus Katayama, 1957.
What does Blackfin Seabass (Hirasuzuki) sushi taste like?
Blackfin Seabass is in season during the cold season, the opposite of Japanese sea bass. Unlike Japanese sea bass, blackfin seabass has a bright red, clear white flesh with no black streaks in the flesh. This makes it look better than Japanese sea bass when served as nigiri or sashimi. Another reason for the high price is that there are few arrivals at Toyosu Market. It used to fetch more than blackthroat seaperch (Nodoguro).
Blackfin Seabass are firm and fatty. Unlike Japanese sea bass, which lives in brackish water, Blackfin Seabass does not have a muddy smell, perhaps because it lives on rough reefs connected to the open sea. It is often described as having a taste similar to Isaki or Tai, for example, with a refined flavor and a sweet aftertaste. It is a top-quality fish that can replace Hirame, which is a representative winter shiromi.
Actually, Shiso (紫蘇) and Ooba (大葉) are the same things.
Shiso (perilla leaf) has green perilla (青紫蘇) with green leaves and red perilla (赤紫蘇) with reddish-purple leaves. Shiso is originally reddish purple in color, and green perilla is a variant of red perilla. The red color of red perilla is due to the pigment shisonin, a type of anthocyanin.
What is Shiso?
Shiso originates from southern China to Myanmar. The shiso is an aromatic Japanese herb and has been used as a condiment in tempura and other Japanese dishes for centuries. Shortly sprouted seeds are called Mejiso (芽紫蘇). The young shoots of green perilla are Aome (青芽), and the young shoots of red perilla are Murame (紫芽).
And Hanajiso (花紫蘇), where about 30% of the shiso flowers are about to bloom. Hojiso (穂紫蘇) is harvested while the fruit is immature. These are also used as garnishes and condiments for sashimi and other dishes.
Why is Shiso called Ooba?
There are two theories. One is to distinguish it from Mejisho, which was used as Tsuma for Sashimi. The young shoots of shiso are Mejisho and the leaves of shiso are Ooba. The other is Ooba, which was adopted as the trade name for the bundles of green perilla leaves that were sold. Since neither of these names is well known to the general consumers, there is no understanding that green perilla and Ooba are the same things.
The many benefits of Shiso
Shiso has one of the highest levels of β-carotene among vegetables. β-carotene is an antioxidant that boosts immunity and protects the body from active oxygen species that cause cancer and atherosclerosis. Shiso is also rich in alpha-linolenic acid. It is converted into DHA and EPA in the body and is believed to prevent aging.
Shiso is rich in iron. Since anemia requires supplementation of iron deficiency, shiso leaves, which are rich in iron, are good food for preventing anemia. It also contains high amounts of calcium, which helps iron absorption.
Shiso contains high levels of potassium, a mineral that helps the body eliminate excess sodium in the urine. By controlling water metabolism in the body, it is expected to reduce swelling.
Perillaldehyde, the aromatic component of green perilla and red perilla, stimulates the secretion of gastric juice, increases appetite, and stimulates gastrointestinal function. red perilla is also used in Chinese herbal medicine to improve gastrointestinal symptoms. It also has strong antiseptic and antibacterial properties. It is often used as a condiment for sashimi tsuma and other dishes because of this potential antimicrobial and sterilizing action, and it is also believed to have some antiseptic properties.
Rosmarinic acid, a type of polyphenol contained in Shiso, is believed to suppress the generation of the active oxygen with its high antioxidant power, making it less likely to cause allergic symptoms. Taking it into the body on a daily basis is expected not only to suppress the aggravation of inflammation but also to make the body less prone to inflammation.
The β-carotene in shiso prevents skin from oxidizing and aging. Calcium, which is abundant in shiso leaves, helps to connect skin cells to each other. It is also rich in vitamin C, which is believed to be effective in whitening the skin.
As a side note, Ooba is often placed between the shari and squid at conveyor-belt sushi restaurants. This is to mask the fishy smell of the squid with the smell of the Ooba.
The Japanese name for the blue rainbow trout is Cobaltmasu, derived from its blue body color. Blue rainbow trout is a mutation in the hatchery production of rainbow trout. This fish lacks the middle lobe of the pituitary gland. This resulted in blue body color. This rare genetic glitch has occurred only in rainbow and brown trout. It is said that one blue rainbow trout is born for every ten of thousand rainbow trout. This trait is inherited recessively. It does not reproduce and is susceptible to disease. Therefore, although it has a beautiful body color, it is difficult to produce in large numbers.
The Albino has no pigmentation. Other Albino fish have a white body color, but the Rainbow trout has a yellow body color. Since its first discovery in 1956 at the Fisheries Experiment Station in Nagano Prefecture, Japan, experiments conducted by crossbreeding Albino with other Albino or Albino with ordinary Rainbow trout have shown that it is genetically dominant. Pure descendants of the Albino are now being produced in aquaculture farms throughout Japan.
Albino is rarely found in the normal production of Rainbow trout in aquaculture farms. Albino is a mutation of the Rainbow trout that lacks tyrosinase (An enzyme that breaks down tyrosine, a type of amino acid, to produce melanin). This prevents the production of melanin, a black pigment, and causes the trout to turn yellow. The yellowish coloration is thought to be due to the other pigments that remain after the melanin-black pigment is gone.
Normal Albino is genetically recessive, so if both parents are not Albino, their offspring will not be Albino. However, Albino rainbow trout is dominant, so if either male or female parent is an Albino, their offspring will be born as an Albino.
Neither the albino rainbow trout nor the blue rainbow trout is a protective color, so if it were to occur in nature, it would have little chance of surviving due to bird damage.
Albino rainbow trout has little edible value but is released for recreational fishing because of its scarcity. In fish farms, it is sometimes used as a visible indicator of growth. There may be some differences in taste, smell, and texture, but these are within the range of individual differences. And Sushi chefs do not use Albino rainbow trout for sushi.
Shiba shrimp (Shiba-ebi) is distributed south of Tokyo Bay on the Pacific Ocean side, south of Niigata Prefecture on the Sea of Japan side, and along the coast of China. It lives in sandy mud at depths of 10 to 30 m in inner bays, and grows to about 15 cm in length. The shell is thin, without stripes, and light yellowish-gray in color. They are also called Akahige (Aka means red and hige means antennae.) in some regions because of their red antennae. The season is from November to March. It was once caught in large numbers off the shiba coast of Tokyo Bay, hence the name shiba-ebi. It is important to note that Shiba shrimp lose their freshness quickly and the heads darken quickly, so they should be cooked on the same day or the heads should be removed. The main production areas are the Ariake Sea in Kyushu and Mikawa Bay in Aichi Prefecture. Its scientific name is Metapenaeus joyneri (Miers.1880).
What does Shiba shrimp (Shiba-ebi) sushi taste like?
Shiba shrimp is generally used in seafood tempura, Chinese cuisine, etc. When made into sashimi, it has a light and elegant taste, but the texture and sweetness are not quite enough.
It is not a typical ingredient for Nigiri sushi, but it is indispensable at sushi restaurants. It is used as an ingredient in Oboro and Tamagoyaki. Rarely, you will see sushi chefs making Gunkanmaki, but it looks grayish-white and not very tasty, and the delicate taste of Shiba-ebi is masked by the flavor of the nori seaweed.
Sweetfish (Ayu) is distributed throughout East Asia from southern Hokkaido to Kyushu, the Korean Peninsula, and northern Vietnam. The species found on Amami-Oshima Island and Okinawa Island is called Ryukyu-ayu and is a differentiated subspecies. Ayu is characterized by the oval yellow spots on the upper pectoral fins and a dozen rows of comb-like teeth aligned on the lip.
It is born near the estuary in the fall, goes down to the sea to overwinter, returns upstream the following spring to become an adult, and then migrates back downstream to spawn and live out their lives. In some lakes, such as Lake Biwa, a land-locked type is found that completes its life in the lake instead of the ocean. These groups are called Ko-ayu. Aquaculture is also popular, with Gifu, Hiroshima, Kochi, and Kyushu being well-known production areas. The scientific name is Plecoglossus altivelis altivelis (Temminck and Schlegel, 1846).
The traditional names used to describe the fish are “Kou-gyo (fragrant fish)“ (because of its unique scent), “Nen-gyo (annual fish)“ (because it usually lives only one year), “Ginko-gyo (silver-lipped fish)“ (because its mouth glows silver when it swims), Keiun (means sardine in a mountain stream) and “Sairin-gyo (scaled fish)“ (because of its small scales).
What does Sweetfish (Ayu) sushi taste like?
Adult ayu feeds on algae on the surface of stones in the river, giving them a distinctive aroma like that of watermelon or cucumber, which can already be smelled even by young fish in the upstream season. The season is from July to August when ayu put on fat, but the aroma is stronger when young ayu are caught a little earlier.
When preparing nigiri sushi, small wild ayu is used, the head and entrails are removed, and the belly is cut open and the inside bone is removed. In traditional Ayu sugata sushi (whole fish sushi), the fish is thoroughly salted to drain off the water and make it strong sujime. Then let it rest in the refrigerator for half a day. If the fish is small ayu, the skin can be left on, but if the size is large or the sushi is to be made immediately after soaking in vinegar, the skin is often felt hard, so it is removed. There are very few sushi chefs who make Ayu’s nigiri sushi, so Sushi Sanshi (鮨三心), Sushi Ikko (鮨一幸), Kanda Sasazushi (神田笹鮨), etc. have it on their signature menu. It was the most popular autumnal sushi item during the Edo period.
To enjoy the elegant appearance and aroma of ayu, grilled with salt is the best way to go. The fish is put on a skewer in such a way that their body forms a wave, making them look as if they are swimming (it is called uneri gushi). It is traditionally eaten with water pepper vinegar, which goes well with it.
Stone flounder (Ishigarei) is distributed along the coasts of Japan, the Kuril Islands, Sakhalin, the Korean Peninsula, and Taiwan. It lives in sandy mud at depths of 30 to 100 meters, and its total length reaches 50 cm. The body surface is smooth with no scales, but there are large longitudinal bony plates on the dorsal surface of the body on the eye side and other small bony plates. In Japan, depending upon the region it will be called other names, such as Ishimochi, Ishimochigarei, or Shirogarei.
It was caught in large quantities by bottom trawling fishing and was synonymous with cheap flounder. However, since the Edo period (1603-1867), it has been treated as a luxury fish in Tokyo. This is because white fish are scarce in summer, and even now, as summer approaches, the price rises along with Japanese sea bass (Suzuki) in the market. However, there was a time when it became a phantom fish that could not be caught at all due to the reclamation and development of Tokyo Bay that began after World War II.
What does Stone flounder (Ishigarei) sushi taste like?
Stone flounder is made by quickly removing the bony plates during the preparation process to avoid the characteristic muddy smell of flounder. It has clear, elegant flesh with a moderate aroma of the sea and a rich flavor with just the right amount of crunchiness. It caught in Tokyo Bay is highly prized and is served as sashimi and sushi, but it is also delicious simmered, or grilled.
As a rule, only live fish can be used for nigiri sushi. Nojime and Ikejime are also not highly valued because the umami component of flounder rapidly decreases after death. Stone flounder, which can be found in abundance in supermarkets at reasonable prices, cannot be used for nigiri sushi or sashimi. It also has a distinctive odor when it is no longer fresh, so it is best to remove it quickly and remove the skin. Skinless fillets can be enjoyed even after maturing for a while.
We’ll start by breaking down the meaning of this word in Japanese.
The “O” of “Omakase” is a prefix generally used as an honorific expression. The meaning of “makase” refers to a judgment of things and means to entrust a task you were meant to do to someone else, allowing them to perform the task at their own discretion. In terms of sushi, while a customer normally chooses which toppings they want to eat on their own, a customer with limited sushi topping knowledge may ask the chef to prepare his own recommendations.
There are various other ways to order sushi toppings as well. First, sushi restaurants generally have a set menu called “Okimari.” For example, let’s consider an Okimari set that contains 8 pieces of nigiri sushi. This set of 8 pieces will contain the same toppings and maintain the same price throughout the year. In contrast, a customer may choose the number of toppings they like in whatever order they prefer, such as ordering two pieces each of four types of toppings, which is called “Okonomi.” They can even order eight of the same topping. The price for “Okonomi” depends on what is ordered, the more expensive the toppings are, the higher the price will be. For “Omakase,” the chef would select 8 toppings and serve them in his recommended order. However, the customer conveys their budget to the chef in advance so the sushi course can be provided within that budget. The customer can also specify toppings they prefer to avoid. In other words, you need to let the chef know in advance about your budget according to the market, and any requests (For example, I would like to eat the Splendid alfonsino (Kinmedai) in season) that you can’t budge on. You don’t need to leave those two things up to the chef’s discretion.
Now, in actuality, there are many sushi restaurants that stray from the original definition of “Omakase.”
For instance, he/she may include Tsumami as part of the course, rather than only sushi. This would be Sushi Kappo (sitting at the counter to enjoy Japanese food and served directly by the chef). A sushi restaurant was once a place where only Nigiri sushi was served. To explain in more detail, if only Nigiri sushi is served, then even if you were to eat 20 pieces of Nigiri sushi, your time in the restaurant would only be around 30 minutes (this is true the case of the establishment of the famous Jiro). Nowadays sushi restaurants are used for entertaining business clients or going on dates, so the customer may stay for around two hours. In situations like this conversation is the priority, so the actual ordering of the sushi takes the backseat. Incidentally, the practice of drinking Japanese sake at sushi restaurants is said to have begun around 1910.
Next, we’ll let you in on a common misconception that you probably don’t want to hear.
Apparently, people believe that ordering Omakase means that you will be served rare pieces that are not disclosed on the menu. Some are even convinced that they can get more expensive toppings than they would if they ordered with the Okonomi method. However, the restaurant just sets the price for the Omakase course and just adjusts the menu items accordingly (to suit the budget) based on current stock. The benefit to the restaurant is that it only stocks the amount of seafood necessary and will waste less. Unfortunately, rare finds are reserved for customers who know what they like. Go ahead and toss any such expectations out of your mind right now. Instead, acquiring sushi knowledge will allow you to avoid being recommended toppings that are approaching expiration.
Finally, if you just get an expensive Omakase course without understanding where the toppings came from or when they are in season, then it won’t contribute to your deeper understanding of the magnificence of Nigiri sushi.
Each food has its own season. It goes without saying that the taste is at its best at that time of year.
When is this “season”?
Most people would answer that it is the time of year when food can be harvested in abundance. This is certainly true for fruits and vegetables. However, this is not always the case with fish. Fish season refers to “the time when the fish is at its peak of fat content,” which does not necessarily coincide with the time when the food is in abundance.
Then, what determines when fish are in season, is the relationship with the spawning season, which is the most important factor. One to two months prior to spawning, both male and female fish feed frantically. This is the time of year when the fish are fat, fatty, and delicious. This is the fish’s season.
However, when the spawning season arrives, the fish become thin. This is because all the nutrients in the body are absorbed by the testes of the males and the eggs of the females. Especially immediately after spawning, the fish have used up all their energy, and their flesh is in a very shabby state.
In other words, the timing of eating the fish is off by just a few days, and the fish tastes considerably less good than when it is in season.
We think you get the idea by now.
You are bound to order fish out of season due to your lack of knowledge. To avoid wasting your money, you should know the season of typical sushi items.
The seasons of typical fish are as follows.
Spring: Japanese halfbeak (Sayori), Ark shell (Akagai), Red seabream (Tai), Pacific herring (Nishin), Black Rockfish (Mebaru), Firefly Squid (Hotaru ika)
Summer: Japanese conger (Anago), Bonito (Katsuo), Horse mackerel (Aji), Greater amberjack (Kanpachi), Goldstriped amberjack (Hiramasa), Daggertooth pike conger (Hamo), Japanese sea bass (Suzuki), Sea urchin (Uni), Japanese whiting (Kisu), Chicken grunt (Isaki), Common scallop (Hotate)
Katsuobushi (鰹節) appears frequently in documents from the Muromachi period (1333-1573) and later, and was used then, as it is now, to take dashi. The name Tosa-bushi is also found in documents from the early Edo period (1603-1868), but the method of making it seems to have been to boil it down and then dry it in the sun, and it is said that the current molding method was invented around 1673~81. In theTosa Domain, which has been famous for bonito fishing since ancient times, Harimaya Sanosuke of Usa and Yamazaki Giemon of Nakahama worked to improve and popularize Tosa-bushi, and the name Tosa-bushi spread as a specialty of the domain in Edo and Osaka.
The process of making katsuobushi begins by boiling the formed bonito meat in boiling water, removing the bones and some of the skin, placing it in baskets, and then placing it in a chamber to be heated and dried over a fire made of oak, sawtooth oak, or kashiwa (oak tree). This is called Baikan (焙乾).
At this stage the product to be shipped is called Namabushi. The first Baikan is called Ichiban-bi. After that, the cracks and missing parts of the Fushi are repaired with bonito surimi. The baikan is repeated once a day for 2 to 12 times. In case you are wondering, Katsuobushi before shaving is called Fushi.
After Baikan, it is called Arabushi (荒節) or Onibushi (鬼節). After drying in the sun for a few days, the surface is scraped with a small knife and called Hadakabushi (裸節), Akamuki (赤むき), Wakabushi (若節), Shinbushi (新節), etc. After drying in the sun again, it is placed in a wooden box called Kabi-tsuke-bako for 15 to 17 days in a cool and dark place, and the surface of the Fushi is covered with blue-green mold. This initial molding is called Ichiban-kabi (一番黴). This process is repeated, and those that have been processed for Niban-kabi are called Aokarebushi (青枯れ節).
This process is usually repeated four times, and when the Yoban-kabi (四番黴) process is completed, the product is called Hongarebushi (本枯れ節). This process is very effective in reducing the fishy smell and fat content of the Fushi and improving its flavor and color.
The best Katsuobushi is the one that is well-dried, has a tortoiseshell-like color, and a clear metallic sound when tapped. When buying katsuobushi with high-fat content or oxidized fat, the surface color may be white or yellowish-brown, so care should be taken when purchasing katsuobushi.
Kezuribushi made by shaving Hongarebushi is called Katsuobushi-kezuri (鰹節削り). On the other hand, shaved Arabushi is called Katsuo-kezuri (鰹削り). Katsuobushi-kezuri has a milder fragrance than Katsuo-kezuri and is relatively light. This is because the mold softens the smoky smell of Baikan and the fishy smell of fish.
Generally, Arabushi is used mainly in Kansai, while Hongarebushi is preferred in Kanto. The reason for this goes back to the Edo period (1603-1867). At that time, Katsuobushi was transported to Edo by sea from western Japan, including Tosa, Satsuma, and Kishu. However, because mold grew during the voyage, it was dried in the sun and eaten, which added a mild aroma. Since then, mold-dried Katsuobushi has been favored in Edo.
Kezuribushi varies in thickness. Usukezuri (薄削り) is 0.1 mm or less and is used as Hana-katsuo (花かつお) for decoration, and is not suitable for making dashi. Nakakezuri (中削り) is around 0.2 mm thick and is generally used at home because it can be used to make dashi in a short period of time. Atsukezuri (厚削り) is about 0.7 mm thick and should be boiled for about 20 minutes to make dashi. Atsukezuri is rarely used by itself but is often blended with several types of Fushi for commercial use.
Kezuribushi is all about the aroma. To prevent volatilization and oxidation of the aroma, it should be sealed in a plastic bag, with the air inside pushed out, and stored in a refrigerator or freezer. Even though it is dry food, it needs to be handled in the same way as fresh food.
Shiokara (salted fish guts) and Gyosho (fish sauce) are widely produced throughout East Asia and are very similar foods in terms of their ingredients and production methods.
Gyosho is made by preserving raw seafood in salt. It is a fermented food in which the raw materials are broken down into amino acids, mainly by the action of enzymes contained in the raw materials, and the umami is intensified. There are solid and liquid products leached from it.
The production process is not much different from that of salted fish, but salted fish is intended for long-term preservation of protein sources, whereas gyosho is produced for use as a seasoning. It is originally obtained as a byproduct of salted fish, but nowadays, it is produced only for the purpose of obtaining Gyosho.
However, most of the Shoyu produced in Japan is made from cereal grains, and the amount of gyosho produced for local consumption is minimal.
Types of Gyosho
Shottsuru has long been produced in the Akita area. Sailfin sandfish (Hatahata) is the most well-known fish used, but Sardine and Pacific sand lance are also used. First, the fish’s head, entrails, and tail fins are removed, and the fish is washed in water. Then the fish is drained, and about 10 kg of fish is mixed with about 1,800 ml of rice malt and 1,800 ml of salt, packed in a wooden barrel, covered with a lid, and weighted down. After maturing in a cool, dark place for about three years, the fish is filtered and boiled to make the product.
Ishiru is made in the Okunoto region. There are other names such as Ishiri, Yoshiru, and Yoshiri. The fish used are sardine, round herring, horse-mackerel, etc. The meat is often processed into dried fish, and the surplus heads and entrails are used. About 30% salt is added to this, packed in miso barrels, covered with a sheet, and aged for six months to a year. After that, it is boiled and filtered to make the product.
Ishikawa Prefecture also produces “Ishiri,” which is easily mistaken for “Ishiru,” but it is made from the entrails of the Japanese common squid.
Nam pla (น้ำปลา)
Nam pla is an essential seasoning for Thai cuisine. In Thai, nam means liquid and pla means fish. In the traditional method, small marine fish, starting with sardine, are mixed with 30~40% salt by weight and placed in a large jar for maturing.
After about a year, a long, thin bamboo basket is inserted into the jar and the liquid that has leached out is drawn out and bottled to make the product. Inland, freshwater fish such as Carp and Loach are used. There is also a theory that the origin of Nam pla is to use freshwater fish.
Gyosho, called garum, was widely used in ancient Rome around the 1st century BC. Bluefish such as mackerel would be pickled in salt, stuffed into unglazed jars, and maturing under the sun. The garum that flowed out through a hole drilled in the bottom of the jar was then used as a seasoning. In Italy, garum production stopped around the 16th century.
Anchovy sauce, a similar product made by maturing salted round herring for six months or more, grinding it, and adding spices, is now used as a secret ingredient in spaghetti and other Italian dishes.
Nước mắm is mainly made from Round herring and Amberstripe scad in Vietnamese Gyosho, and Carp, Loach and Catfish fry are also used around the Mekong Delta. The cleaned fish is placed in a container with 10~15% salt by weight, stirred every morning, and salt is gradually added until it reaches a concentration of about 30%, depending on the progress of maturing. Those aged for one year or more are more delicious. Gyosho from Đảo Phú Quốc is considered the best.
Colatura is an Italian Gyosho. It is made from nothing but round herring and salt. The round herring is first removed from the head and entrails and placed in a barrel, alternately layered with salt. Then, a wooden lid is placed on the herring, and weights are placed on top of it for maturing.
After maturing for three to four years, a hole is drilled in the bottom of the barrel and the Colatura is slowly extracted, drop by drop, over time. The slow aging process in the barrels concentrates the flavor of the fish and produces the amber-colored Colatura.
Shinanoyuki-masu (信濃雪鱒) is a cold-water fish classified in the genus Coregonus, which is related to salmon, and was not originally from Japan.
In 1975, eggs were introduced to Nagano Prefecture from former Czechoslovakia, and after 10 years of testing and research at the Nagano Prefectural Fisheries Experiment Station, the prefecture succeeded in establishing the world’s first aquaculture technology.
In 1983, full-scale production began on a private-sector basis, and the fish was named Shinanoyuki-masu (shinano means ‘Nagano prefecture’, yuki means ‘snow’, and masu means ‘trout’), an appropriate nickname for its silvery-white appearance reminiscent of snow.
The neighboring Saku Aquaculture and Fisheries Cooperative Association also sell sturgeon roe under the name Golden caviar after separating the muscle-like roe into pieces and marinating them in salt. However, this is not a Golden caviar, but rather a Yellow caviar.
Generally, River trout, Char, Yamame, and Amago, which grow only in rivers and lakes, do not take red pigments, so their eggs themselves remain yellow. Yellow is also associated with roes but can also come from an albino fish. Rainbow trout is almost always orange, but can also be yellow using a feed that does not contain astaxanthin.
Tsukudani (佃煮) is a type of processed food made by simmering small fish caught at the seashore or lakeshore in seasonings. Tsukudani is boiled down in a seasoning solution consisting mainly of soy sauce and sugar, so it can be kept for a long time. In addition to the sterilizing effect of heating, the osmotic pressure created by the salt in the soy sauce reduces the water content in the tissue. This reduces the proliferation of bacteria and thus preserves the fish.
The marine products used to make Tsukudani include small fish such as Spiny goby (Haze), Pacific sand lance (Konago), Half mouth sardine (Shirasu), Crucian carp (Funa), Bitterling (Tanago), and Japanese smelt (Wakasagi); diced Bonito (Katsuo) and Tuna (Maguro); shellfish such as Baby clam (Asari), Orient clam (Hamaguri), and Bloody clam (Akagai); crustaceans such as Shrimp (Ebi) and Mysid (Ami); and seaweeds such as Kombu and Nori. Shio-kombu is also a type of Tsukudani.
For Tsukudani, the freshest ingredients are chosen. If small fish are used that are not fresh, their flesh will fall apart and the seasoning will become cloudy, reducing the value of the product.
When making Tsukudani, the first step is to bring water, soy sauce, sugar, and other seasonings to a boil in an iron cauldron. The ingredients are then placed in the pot and simmered over low heat to allow the liquid to absorb into the tissues of the ingredients. After the simmering process, the Tsukudani is removed from the cauldron and cooled quickly by blowing air through a fan or similar device. The reason for this is that prolonged heat will cause the quality of the product to deteriorate.
The name Tsukudani is said to have originated with fishermen on Tsukuda Island (佃島) during the Edo period (1603-1868), a small island at the mouth of the Sumida River, which flows into Edo Bay. It was named Tsukuda Island after a group of fishermen from the village of Tsukuda in Settsu (摂津), who were invited to settle there when the Edo shogunate was established.
Since Edo’s traditional fishing industry was underdeveloped then, Tokugawa Ieyasu is said to have introduced advanced fishing techniques from the west to supply food for the urban population of Edo.
Tsukuda Island fishermen delivered fish to Edo Castle and the lords. On the other hand, small fish that had no commercial value were seasoned and processed for their use.
Their taste became so well known that they came to be called Tsukuda-ni (ni means simmer) after the name of the land. Tsukudani was a way to make effective use of small fish without discarding them and preserving them.
These Tsukudani were brought back to the country as souvenirs by the samurai on the “Sankinkotai (duty of alternate-year attendance in Edo)”. Eventually, local producers began to follow their example, and it spread throughout the country.
Tsukudani has several variations. Shigure-ni (時雨煮) is made by cooking flaked clams, clams, and other shellfish with soy sauce as well as sansho (Japanese pepper) and ginger. Shigure-hamaguri (時雨蛤) is a specialty of Kuwana, Mie Prefecture. Kanro-ni (甘露煮) is soy sauce with more syrup added and boiled down until there is no more liquid. Ame-ni (飴煮) is made by adding sake and mirin to soy sauce, simmering the ingredients in the seasoning liquid, and then adding more syrup. In the past, Ame-ni was often made with river fish such as crucian carp. In recent years, sugar and syrup have been used in Tsukudani, and the distinction between Kanro-ni and Ame-ni seems to have become ambiguous.
Toro salmon, Toro Katsuo, Toro Sawara, Toro saba, Buri toro, Beni toro, and Toro, the original maguro, have all been added to the list, and the number of fish calling themselves Toro, other than maguro, is increasing.
In other words, the word Toro is becoming increasingly generic.
Anyone who has endured the advertising onslaught of the modern era knows that word “toro” always seems to make its way into marketing materials. The word is meant to convey a luxury ingredient, and the “gotta-eat-it” mentality that drives sales.
For example, Toro saba (Saba means ‘mackerel’) is a fatty mackerel. Speaking of fatty mackerel in Japan, the first thing that comes to mind is Norwegian mackerel (Atlantic mackerel). It was once criticized for being too fatty for some unintelligible reason.
In Norway, the amount of mackerel that can be caught in a year is strictly regulated by each fishing boat, so they only catch mackerel when it is fatty and the price is high. Japanese chub mackerel has a peak fat content of 20-25%, while Norwegian mackerel has a peak fat content of 25-30%.
The term “fatty” is often used to describe the meat and taste of the fish. This term, of course, implies a high fat content, but the real message we wanted to convey was supposed to be “tasty”. This is because fat contains many flavor compounds. However, literally fatty fish is appreciated and it has become a first-class citizen.
The increase in fatty farmed fish and imported fish such as Northern mackerel may have played a role in this trend, and at the bottom of it all, as with the Toro worship of tuna, there has been a major shift in Japanese eating habits in the postwar period.
In this naming, we cannot help but feel the commercial spirit and skill of the company, which has successfully turned what could be a disadvantage into an advantage by combining changing tastes with the sense of luxury that the word “Toro” possesses.