1. Introduction

Around Doyo no Ushi no Hi (Midsummer day of the ox), lines form outside eel restaurants across Japan, and even Tokyo fishmongers start grilling eels at their counters—something they don’t usually do. On this day alone, even those who aren’t eel lovers strangely crave it, happily reaching out for eel. Eels have been objects of worship due to their unique appearance and astonishing vitality, and treated as medicine because of their high nutritional value.

Japan, blessed with numerous rivers, lakes, and wetlands, has long provided an ideal habitat for eels. Eel bones have been unearthed from Jomon-period archaeological sites, and the Man’yōshū anthology contains a poem by Ōtomo no Yakamochi celebrating eel cuisine. However, the specific way to eat unagi is unknown.

Records of eel cuisine first appear in compiled form during the Muromachi period (1336-1573), with “Namasu (raw fish slices)” and ‘kabayaki’ documented in texts. The kabayaki of that era involved grilling chunks of eel, then brushing them with soy sauce and sake before cooking. Later, during the mid-Edo period, a method emerged where the eel was split lengthwise to drain excess fat while grilling, establishing the kabayaki we know today as a “delicacy.” Its popularity exploded during the Genroku period in Edo.

Even then, however, street stalls and vendors were still the main purveyors. The first dedicated unagi restaurants appeared in 1777. Within just a few decades, guidebooks were published, sparking lively discussions among connoisseurs about which shops were best and which regions produced the finest eels. The custom of eating eel on Doyo no Ushi no Hi also spread around this time.

Eventually, the “Morisada manko (守貞漫稿)” (1837-53) detailed the preparation methods for grilled eel in Edo, Kyoto, and Osaka, reaching a form nearly identical to today’s.

Farming began in the Meiji era (1868-1912), shifting the scene from Tokyo’s Fukagawa to Lake Hamana. By the early Showa period (1926-1989), much of the eel grilled in Tokyo came from regional sources or was farmed.

Today, over half of the eel in circulation is processed products from China. Supermarkets stock inexpensive eel year-round, and the old saying that “eel costs ten times as much as soba” has become a distant memory.

 

 

2. What exactly is Unagi?

Basic Information and ecology of the Japanese eel

Anguilla japonica, commonly known as the Japanese eel, is a species of freshwater eel native to East Asia. It plays a central role in Japanese cuisine, especially in dishes like unaju (grilled eel over rice in a lacquer box) and unadon (served in a bowl).

There are 19 species of eels inhabiting the world, including the Japanese eel. Among these, the main species consumed for food are the Japanese eel eaten by the Japanese, the European eel, the American eel, the Bicarra species found in Southeast Asia, and the Marmorata species. They are listed below.

What makes this eel fascinating is its mysterious life cycle. Japanese eels are catadromous, meaning they live in freshwater rivers and lakes but migrate to the ocean to spawn. Scientists believe they travel thousands of kilometers to the deep waters of the Mariana Trench, where they reproduce—a journey that remains only partially understood even today.

Incidentally, when people hear “migratory fish,” they often think of tuna or bonito swimming in the open ocean. In fact, eels are also migratory fish. Among migratory fish, there are different classifications. Fish that travel between rivers and the sea are called migratory fish. Fish like salmon, which grow in the sea and spawn in rivers, are called anadromous fish. Fish like eels, which grow in rivers and spawn in the sea, are called catadromous fish.

After hatching, the tiny transparent larvae called leptocephali drift on ocean currents toward East Asia. Eventually, they reach coastal areas of Japan, Taiwan, and China, where they are caught as young “glass eels” and raised in aquaculture farms or, in rare cases, continue upstream as wild eels.

In Japanese food culture, this species is prized not only for its rich, fatty flavor but also for its symbolic associations with strength, stamina, and seasonal tradition.

 

・Tropical Indo-Pacific species

Anguilla celebesensis Kaup, 1856 (Celebes longfin eel)

Anguilla megastoma Kaup, 1856 (Polynesian longfin eel)

Anguilla interioris Whitley, 1938 (Highlands longfin eel)

Anguilla reinhardtii Steindachner, 1867 (speckled longfin eel)

Anguilla marmorata Quoy & Gaimard, 1824 (giant mottled eel)

Anguilla nebulosa McClelland, 1844 (mottled eel)

Anguilla borneensis Popta, 1924 (Borneo eel)

Anguilla mossambica (W. K. H. Peters, 1852) (African longfin eel)

Anguilla bicolor bicolor McClelland, 1844 (Indonesian shortfin eel)

Anguilla bicolor pacifica E. J. Schmidt, 1928 (Indian shortfin eel)

Anguilla obscura Günther, 1872 (Pacific shortfinned eel)

Anguilla bengalensis bengalensis (J. E. Gray, 1831) (Indian mottled eel)

Anguilla bengalensis labiata (W. K. H. Peters, 1852) (African mottled eel)

Anguilla luzonensis S. Watanabe, Aoyama & Tsukamoto, 2009 (Philippine mottled eel)

 

・North Atlantic and Pacific Temperate Species

Anguilla rostrata (Lesueur, 1817) (American eel)

Anguilla anguilla (Linnaeus, 1758) (European eel)

Anguilla japonica Temminck & Schlegel, 1847 (Japanese eel)

 

・South Pacific temperate species

Anguilla dieffenbachii J. E. Gray, 1842 (New Zealand longfin eel)

Anguilla australis australis J. Richardson, 1841 (short-finned eel)

Anguilla australis schmidti Phillipps, 1925

 

3. What does Unagi taste like?

3-1 Unagi taste

The taste of Japanese eel varies by the type of eel and how it’s prepared—sometimes crispy, sometimes chewy—but it is often salty, slightly sweet and meaty. The most popular way of eating Japanese eel is to grill it with a sweet and savory sauce called “kabayaki sauce,” made of soy sauce, mirin, sugar and sometimes sake.

Eel is the river fish with the toughest skin. Tough skin raises both the bar for deliciousness and the difficulty of cooking. In other words, the history of eel cuisine is also the history of “how to make it plump and tender.” Learning about eel dishes from different regions, one cannot help but admire the wisdom of our predecessors.

In the Kanto region, the process of steaming after initial grilling was added in the Meiji era, establishing a technique now widely recognized as defining the Kanto style: a fluffy, melt-in-your-mouth texture. That said, other methods exist in Kanto to achieve tenderness.

One method involves boiling the eel in a pot instead of steaming it after initial grilling. This softens it faster than steaming, resulting in a flavorful, plump texture. Another method is “box steaming,” where the grilled eel is placed in a box, steamed using residual heat, and then finished over binchōtan charcoal.

Kantō also has another technique called “raw steaming,” where the prepared eel is steamed raw without initial grilling. This preserves the eel’s natural flavor and yields a firm, springy texture.

In Osaka, there’s a dish called “mamushi,” which at first glance appears to be just rice in a bowl. Its name comes from “ma-mushi” (steaming between layers of rice). Nowadays, kabayaki is also placed on top of the rice.

Kyushu has “seiro (steaming basket)-mushi.” Rice is steamed with sauce, then grilled kabayaki and shredded egg are placed on top of the rice, and it’s steamed again. The eel becomes plump, and the rice becomes sticky.

 

3-2 What is Shinko?

In general, shinko refers to a sushi term for young kohada (gizzard shad). These small, tender fish are prized for their delicate flavor.

When it comes to eel, however, shinko has a different meaning. It refers to eels that were stocked as glass eels in ponds around December and are ready for harvest by the following December. These young eels have exceptionally soft flesh, fine bones, and are easy to eat. They are considered a rare summer delicacy, typically enjoyed from June to July.

At eel farms, eels are periodically sorted by size and transferred to new ponds several times as they grow. Differences in growth rate are largely due to how much feed each eel consumes. Among shinko, those that grow especially quickly are called tobi (トビ). The faster an eel grows, the softer its flesh and skin become. Tobi eels also have a rich layer of fat, fewer fine bones, and a wonderful aroma, leaving a clean, refined aftertaste.

Eels raised for more than a year, on the other hand, are known as hineko (ヒネ仔). Their skin becomes firmer and their bones thicker, but they develop a deeper, more mature flavor that young eels lack.

In the end, whether one prefers the freshness of shinko or the richness of hineko comes down to personal taste.

 

3-3 Health benefits of unagi

Please refer here

 

4. How Unagi Is Prepared: Grilling, Sauces, and Styles

4-1 Kanto vs Kansai unagi

Even familiar dishes can differ significantly between the Kanto and Kansai regions, reflecting their distinct histories and climates. Eel kabayaki is one such example. The Kanto style involves splitting the eel lengthwise, the head is removed, and the body is cut in half. It is then skewered, and grilling without seasoning. It is then steamed and grilled again. In contrast, the Kansai style involves cutting the eel open along the belly without removing the head, skewering it on an iron skewer, and grilling it without steaming. Skilled chefs deftly handle the long skewers, flipping the eel repeatedly as if folding it over and over.

The difference in preparation reflects regional culture and history. In Edo, where samurai were numerous, belly-cutting was avoided as it evoked associations with seppuku (ritual suicide). Thus, back-cutting became the norm. Conversely, in Kansai, where merchant culture was deeply rooted, belly-cutting is said to have originated from the phrase “opening one’s belly to speak frankly,” symbolizing honesty and trust. While this sounds plausible, the historical text “Morisada Manko (守貞漫稿)” explicitly states “Edo uses belly-cutting.” Upon reflection, even in Kanto, other fish have their innards removed by cutting open the belly. So perhaps it’s best not to get too caught up in the details.

 

4-2 Characteristics of the Sauce

The sauce is what ultimately defines the eel’s flavor profile—its taste, of course, but also its savory aroma, the glossy sheen of its appearance, and the overall appeal. Eel sauce is made by combining soy sauce and mirin, then simmering it down with added sugar, sake, and other ingredients. While these are all familiar seasonings to Japanese people, the flavor varies depending on the manufacturer and brand used. Furthermore, even using the same brand and quantities, each restaurant varies the simmering time and timing of when ingredients are added. This process embodies the craftsmanship and dedication cultivated through the restaurant’s history. The sauce is continuously replenished as it is used to glaze the carefully grilled eel, allowing its depth of flavor to build over time, becoming a truly unique sauce. Precisely because it cannot be perfected overnight, the sauce is often considered the very lifeblood of an eel restaurant.

Just as eel preparation methods vary by region, so does the sauce. The “Morisada Manko,” a late Edo period record of customs in the three major cities, notes : “Edo mixes mirin into soy sauce, while Kyoto and Osaka mix sake into soy sauce.”

At Tokyo’s long-established eel restaurants, inheriting the Edo tradition, a sauce with equal parts soy sauce and mirin remains the standard. In the Kansai region, a richer sauce is used to complement their juicy, grilled eel. Even within the Kanto style, the sweetness of the sauce tends to increase as you move from Tokyo to its suburbs. Among Kansai styles, the Tokai region often features shops using tamari soy sauce and the mellow Mikawa mirin. In Kyushu, where a sugar-rich culinary culture took root during the Edo period through trade at Nagasaki’s Dejima, favors a sweeter sauce.

 

How to Make Eel Sauce (Unagi Sauce)

Ingredients:
・200 ml dark soy sauce
・200 ml mirin (sweet cooking rice wine)
・40 g sugar
・Heads and bones of 2 eels

Instructions:
1. Place the eel heads and bones in a small saucepan. Add the mirin and bring it to a gentle boil over medium heat. Simmer for about 2 minutes to evaporate the alcohol.
2. Add the sugar and stir until it dissolves completely.
3. Pour in the dark soy sauce. Continue to simmer over low heat for about 10–15 minutes, stirring occasionally, until the sauce thickens slightly.
4. Skim off any scum that rises to the surface, then strain out the eel heads and bones using a fine mesh sieve.
5. Let the sauce cool. It will thicken further as it cools.
6. Store in a clean glass jar or bottle in the refrigerator for up to 2–3 weeks.

Tip:
Before using, grill the eel heads and bones thoroughly until well browned. If they are undercooked, they can cause a fishy smell.

 

 

5. Popular Unagi dishes you should try

5-1 Unagi kabayaki (鰻の蒲焼き)

During the Edo period (around 1781–1788), eel was often enjoyed whole-roasted—either coated with sansho pepper miso or flavored with a bean miso oil. One theory suggests that the name kabayaki originated because the skewered, grilled eel resembled cattail spikes (kaba).

Over time, the cooking method evolved: the eel was split open along the back, skewered, steamed to remove excess fat and tenderize the flesh, then grilled with a rich soy-based glaze. This marked the beginning of modern unagi kabayaki. Originally served without rice, it later became known as unadon or unaju when paired with rice.

Kabayaki is considered a type of teriyaki and one of the classic dishes of Edo (old Tokyo). The term can also refer to other foods prepared in a similar style or glazed to resemble it, such as yakitori kabayaki (grilled chicken kabayaki).

 

5-2 Unaju (鰻重)

Unaju is a traditional Japanese dish featuring unagi kabayaki (grilled eel glazed with a sweet soy-based sauce) served over freshly steamed rice in a tiered lacquered box called a jubako (重箱).

The name unaju comes from combining unagi (eel) and jubako (lacquered box), reflecting the distinctive container in which the dish is served.

 

5-3 Unadon (鰻丼)

Unadon is essentially the same dish as unaju, except that it is served in a bowl rather than a lacquered box.

The origin of Edo’s eel kabayaki restaurants is said to trace back to Yamato-ya (大和屋) in Ueno, founded around 1700. At the time, kabayaki was served as a side dish to accompany sake. Customers who didn’t drink alcohol were allowed to bring their own rice. Eventually, the restaurant began offering plain white rice alongside the eel, calling it “tsukemeshi.” Later, Oonoya (大野屋) in Ningyocho introduced “unagi-meshi” (eel over rice), which quickly became a sensation. The dish is said to have been invented around 1810 by Okubo Imasuke (大久保今助).

Imasuke, originally a farmer from Ibaraki Prefecture, prospered as a merchant after moving to Edo and became a financier for the Nakamura-za theater in Ningyocho. One day, while waiting for a boat to return to his hometown, he ordered kabayaki and a bowl of rice at a teahouse. Just as his order arrived, the departure signal sounded. With no time to spare, he borrowed a plate from the shop, placed the kabayaki on top of the rice bowl, covered it, and boarded the boat. When he opened it on the other side, he found that the eel had been perfectly steamed by the heat of the rice, and the sauce had soaked through, creating a wonderfully rich flavor.

Back in Edo, Imasuke, who usually had kabayaki delivered from Oonoya to the theater, complained that it always arrived cold. He instructed Oonoya to deliver the eel placed over rice and covered with a lid. When the restaurant served this new style to other customers, it was an instant success—“You can enjoy it warm and delicious!” Soon, other eel shops followed suit, sparking an “eel rice” boom throughout Edo. Because kabayaki tends to harden when it cools, this accidental discovery proved to be a brilliant innovation. Thus, unadon was born.

 

5-4 Hitsumabushi (ひつまぶし)

If you ask any Japanese person to name a food from Nagoya, hitsumabushi is likely to be one of the first that comes to mind. When visiting Aichi Prefecture, this is one local specialty you simply can’t miss.

Hitsumabushi is a dish of grilled eel served over rice in a wooden container, accompanied by condiments such as green onion, nori seaweed, and wasabi, as well as sencha green tea or dashi broth for making ochazuke (tea- or broth-soaked rice).

One restaurant often credited as the originator of hitsumabushi is Atsuta Horaiken (あつた蓬莱軒), founded in 1873. When the restaurant first began offering delivery, their ceramic bowls frequently broke in transit. To solve this, they started sending grilled eel in wooden rice boxes. Later, they began slicing the eel into thin strips for easier serving. The dish became so popular that it was incorporated into their kaiseki course meals. Seeking to provide a light finish, they also introduced condiments and the tea-soaked eating style that defines hitsumabushi today.

Another restaurant credited with the creation of hitsumabushi is Ibasho (いば昇), founded in 1909. At the time, the wild eels they used varied in size and texture—some were too tough to serve to customers. To prevent waste, the staff finely chopped these eels, mixed them together in a large wooden tub, and enjoyed them as staff meals. This is said to be another origin story.

There’s also a theory that the staff-meal version of hitsumabushi began in Tsu City, Mie Prefecture. However, Nagoya was the first to serve it to customers, establishing it as a local specialty. The existence of several origin stories only underscores its enduring popularity.

 

Here’s the proper way to enjoy it:

① Divide the rice in the tub into four equal portions so you can neatly transfer them to your bowl.
② For the first serving, enjoy the eel’s pure flavor and its crispy-yet-fluffy texture as is.
③ For the second, add green onions, nori, wasabi, and other condiments to taste.
④ For the third, add the condiments, pour dashi broth or sencha (green tea) over it, and enjoy it as ochazuke (tea-soaked rice).
⑤ For the fourth, eat it however you like.

 

5-5 Shirayaki (白焼き)

Shirayaki refers to eel that is grilled without seasoning, before being coated in sauce to become kabayaki. In other words, it’s kabayaki without the sauce—a preparation that allows you to fully appreciate the natural flavor of the eel itself.

The flavor of eel varies depending on its origin and habitat. Because shirayaki is simply grilled, you can truly taste the craftsmanship at every stage—from the eel farmers and wholesalers to the skilled chefs who prepare it.

It can be enjoyed plain or with a light touch of salt, wasabi, or other condiments. The grilling style also differs by region: in Kanto, people enjoy the tender, slightly sticky texture, while in Kansai, the crisp, crunchy skin is prized even more than kabayaki. Shirayaki also pairs beautifully with sake.

 

5-6 Kimosui (肝吸い)

While “liver” generally refers to the liver organ, in the case of eel, it encompasses all the internal organs, mainly the stomach and intestines. Proper preparation is essential to enjoy eel liver safely and deliciously. The organs must be thoroughly rinsed to remove any blood and the small bitter sacs, which contain bile and are extremely bitter. In addition, eel blood and these glands contain a protein-based toxin called ichthyotoxin, so the organs must be carefully washed and parboiled before use. Kimosui is a clear soup made with these pre-prepared eel organs as its base.

The way kimosui is prepared can vary greatly—from whether the liver is boiled or grilled, to the choice of accompanying ingredients, and even the flavor of the broth itself. It is said that a restaurant’s character is revealed through its kimosui. West of Nagoya, diners may even have the option to choose between kimosui and red miso soup. This light, refreshing soup is typically garnished with mitsuba (a Japanese herb with a crisp aroma), offering a perfect contrast to the rich, fatty flavor of grilled eel. In this way, kimosui serves as a delicate palate cleanser that completes the dining experience.

 

5-7 Umaki tamago (う巻き玉子)

Umaki is a type of tamagoyaki (rolled omelet) that has grilled eel (unagi) in the center. Tamagoyaki on its own is delicious, but when combined with unagi and a touch of sweet tare sauce, it reaches a whole new level of flavor.

In Japan, “tamagoyaki” can mean slightly different things depending on the region. In Kanto, it usually refers to atsuyaki tamago (a thick, slightly sweet omelet that’s lightly browned), while in Kansai it means dashimaki tamago (a fluffy omelet made with dashi broth, typically without browning). This difference also affects umaki: Kanto-style umaki tends to pair savory grilled eel with sweet tamago, whereas Kansai-style pairs sweet eel with a more subtly seasoned omelet.

Some restaurants use whole fillets of eel, while others use sliced or minced pieces. Rolling techniques also vary—some chefs make it round, others square—reflecting each restaurant’s unique style and tradition.

 

5-8 Uzaku (うざく)

Uzaku is a refreshing vinegar-based dish featuring grilled eel and cucumber, regarded as a local specialty of Mie Prefecture. The rich, savory flavor of the eel contrasts beautifully with the crisp, cool taste of cucumber, making it an ideal dish for summer.

The preparation of uzaku varies widely from restaurant to restaurant. Even the kabayaki eel used in the dish differs in cooking method and sauce, and the way it is sliced depends on the chef. Some establishments even use shirayaki (grilled eel without sauce). The cucumber may be thinly sliced or julienned, creating different textures and mouthfeel.

And above all, the restaurant’s character shines through in its seasoned vinegar. Some use sanbaisu—a blend of vinegar, soy sauce, and mirin or sugar in roughly equal parts—while others prefer a sweetened vinegar made by adding extra mirin or sugar. Still others make Tosa vinegar, which combines sanbaisu with dashi made from bonito or kelp. Each style produces a distinct flavor. Some chefs also add seaweed, myoga, or ginger for extra aroma and freshness.

 

5-9 Tsukemono (漬物)

Unaju or eel course meals are always accompanied by tsukemono (Japanese pickles). Among them, nara-zuke is the one most closely associated with eel restaurants. There are several theories as to why, but the most widely accepted explanation lies in its connection to Doyō no Ushi no Hi (the midsummer “Day of the Ox”).

Traditionally, it was believed to be beneficial for one’s health to eat foods beginning with the letter “U” on this day. The Edo-period scholar Hiraga Gennai popularized the idea of eating unagi (eel), and since nara-zuke pickles are made from uri (gourd), which also starts with “U”, they naturally became part of the custom as well.

Nutritionally, the pairing makes sense: antioxidants in the pickles help the body absorb the vitamins found in eel. On the other hand, the common belief that unagi shouldn’t be eaten together with uri (watermelon) or umeboshi (pickled plums) is purely superstition with no medical basis. Such folklore surrounding eel shows just how deeply this food has been cherished in Japan for centuries.

 

5-10 Mizugashi (水菓子)

In a traditional eel course meal, the final course is Mizugashi, fresh seasonal fruit served as a light dessert. Fruits rich in vitamin C are said to enhance the absorption of iron and collagen found in eel, making them the perfect way to finish the meal.

 

5-11 Eel Kabuto yaki (鰻兜焼き)

Unagi kabutoyaki is a dish made by skewering and grilling the head of an eel. The name comes from the fact that the eel’s head resembles a kabuto, a traditional samurai helmet. Rich in fat and full of concentrated umami flavor, it’s considered a delicacy. In the Kansai region, the eel’s head, its “helmet”, is known as Hansuke (半助).

 

5-12 Hire (鰭)

Hire refers to the eel’s dorsal fin. This part is rich in collagen and offers a savory, fatty flavor. In the Kanto region, where eels are split open along the back, this portion is typically removed. At eel skewer restaurants, dorsal fins, belly fins, and small pieces around the tail—usually from about ten eels—are rolled together and skewered. Some places add nira (garlic chives) in the center for extra aroma and flavor.

 

5-13 Bara (バラ)

Bara refers to the meat attached to the ribs. It’s comparable to the nakaochi cut of tuna or the kalbi cut of beef, and is a popular choice for eel skewers. The meat along the backbone is called Shiro bara.

 

5-14 Kimo yaki (肝焼き)

Kimo yaki refers to grilled eel liver. Naturally, each eel provides only one liver, so about ten are typically skewered together before grilling. The result is a rich, slightly bitter delicacy often enjoyed with sake.

 

5-15 Hone (骨)

Hone means the backbone of an eel. When the bones are deep-fried until light and crispy, they become honsenbei or “eel bone crackers”, a perfect snack to enjoy with sake.

 

5-16 Unagi sushi (鰻寿司)

In Tokyo, unagi nigiri sushi is almost never found. One theory is that in the Edo period, sushi was sold from street stalls that lacked the proper equipment for grilling eel.

 

6. Where to Eat Unagi in Japan

6-1 Best unagi restaurant in Tokyo

【Hashimoto (はし本)】

Founded in 1835, Hashimoto is a renowned eel restaurant where the sixth-generation owner continues to preserve the traditional flavors of this historic establishment. While techniques like filleting, skewering, and grilling over binchotan charcoal are fundamental, one of the restaurant’s greatest passions lies in its meticulously selected eels. Rather than fixating on a specific place of origin, what truly matters is how well the eel harmonizes with the restaurant’s secret sauce. The use of larger eels called Hineko—around 2.5 per kilogram, a size rarely seen elsewhere—further enhances the sauce’s depth and character, perfectly embodying the spirit of a long-established restaurant whose flavors have been refined over generations.

 

Price: 4,000 JPY – 4,800JPY (Unaju)

Business Hours: 11:30 – 14:30 / 16:30 – 20:00

Tel: +81-3-3811-4850

Address: 2-5-7 Suido, Bunkyo-ku, Tokyo, 112-0005

Regular Holidays: Thursdays / One Wednesday per month

HP: Hashimoto (はし本)

 

6-2 Recommended restaurants in Kawagoe

【Unagi Ogakikku (うなぎ小川菊)】

Founded in 1807 during the late Edo period, “Ogakiku” is a long-established restaurant in Kawagoe specializing in grilled eel. The current proprietor represents the seventh generation of the family. The present building, constructed in 1924, is one of the few remaining three-story wooden structures in the city and has been designated by Kawagoe City as an “Important Urban Landscape Building.”

 

Price: 3,950 JPY – 6,500JPY (Unaju)

Business Hours: 11:00 – 14:00 / 16:30 – 19:30

Tel: +81-49-222-0034

Address: 3-22 Nakamachi, Kawagoe City, Saitama Prefecture, 350-0065

Regular Holidays: Thursdays (except national holidays) & occasional irregular closures

HP: Unagi Ogakikku (うなぎ小川菊)

 

6-3 Recommended restaurants in Nagoya

【Atsuta Houraiken (あつた蓬莱軒)】

Hitsumabushi, a Nagoya City specialty, is a traditional eel dish served over rice in an ohitsu (a round wooden container), accompanied by condiments and dashi (a light Japanese broth). While Hitsumabushi can be found on menus at other restaurants, it is actually a registered trademark and was originally created here at Houraiken.

Founded in 1873, Houraiken serves its signature Hitsumabushi with three condiments—green onion, wasabi, and dried laver—alongside a bonito- and soy sauce–based dashi. The restaurant’s secret sauce, passed down since its founding, adds a rich, distinctive flavor. Discovering your own favorite way to enjoy authentic Hitsumabushi at Houraiken is a truly delightful experience.

 

Price: 4,950 JPY – 6,600JPY (Hitsumabushi)

Business Hours: 11:30 – 14:00 / 16:30 – 20:30

Tel: +81-52-671-8686

Address: 503 Kobe-cho, Atsuta Ward, Nagoya City, Aichi Prefecture, 456-0043

Regular Holidays: Wednesday, 2nd and 4th Thursday

HP: Atsuta Houraiken (あつた蓬莱軒)

 

6-4 Recommended restaurants in Sendai

【Unaki (うな貴)】

Located near Sendai City Hall and Ichibancho Shopping Street, Unaki is a Kanto-style eel restaurant that incorporates a steaming process in its preparation. Using authentic Kishu binchotan charcoal and traditional shichirin grills, it faithfully preserves the flavors of a time-honored establishment. From the careful selection of eels to expert grilling, guests can savor the refined taste of this renowned Sendai restaurant.

 

Price: 4,800 JPY – 9,200JPY (Unaju)

Business Hours: 11:00 – 14:00 / 17:00 – 20:00 (Closes when sold out)

Tel: ＋81-22-265-8650

Address: 3-2-18 Kokubuncho, Aoba-ku, Sendai City, 980-0803

Regular Holidays: Irregular holidays

HP: Unaki (うな貴)

 

 

7. When to Eat Unagi: Seasonal Traditions and Timing

The custom of eating eel on Doyo no ushi no hi (Midsummer day of the ox) is said to have begun around the middle of the Edo period. While there are various theories about its origin, the most well-known is that Hiraga Gennai (平賀源内) devised a marketing strategy for eel, which didn’t sell well during the summer.

Discerning Edoites considered eel from autumn to winter, before spawning, when it was rich in fat, to be at its best. Consequently, summer eel was unpopular. So, one eel shop owner consulted the knowledgeable Master Gennai. Gennai suggested posting a sign reading “Today is Ushi no Hi” at the shop entrance. Well-versed in herbal medicine, Gennai connected eel to the ancient belief that eating foods starting with ‘U’ on the day of the ox (Ushi no hi) would restore vitality. The result? The shop became wildly popular. As eel shops throughout Edo copied this tactic, “the custom of eating eel on Doyo no ushi no hi spread rapidly.”

However, there is no definitive proof that Hiragane Gennai was the one who popularized it. A document written around 1822 states that the custom of eating eel on doyo no ushi no hi began around 1780. It also mentions that the custom existed not only in summer but also on the winter doyo no ushi no hi.

Although the doyo period occurs four times a year at seasonal transitions, the summer doyo has become firmly associated with eel consumption. Every July, “doyo no ushi no hi” banners across Japan appear, sparking purchasing interest even among non-eel enthusiasts. In fact, July sees the highest annual sales of kabayaki eel for home consumption.

Meanwhile, some eel restaurants close on Doyo no Ushi no Hi. Koji Hattori, owner of Una Toyo in Mizuho Ward, Nagoya City, visits Choraku-ji Temple in the city every year to perform a memorial service for eels.

 

8. Sustainability challenges for the Japanese eel

Despite its popularity, unagi faces significant sustainability challenges. Overfishing, habitat loss, and climate change have led to a dramatic decline in wild eel populations. Glass eels (juvenile eels) are particularly vulnerable, dropping their numbers to less than 10% of their historical levels. The Japanese eel (Anguilla japonica) is now listed as an endangered species by the IUCN, reflecting the seriousness of this decline.

In addition to overfishing, river construction and dam building have disrupted traditional migration routes, while changes in ocean currents—such as shifts in the Kuroshio Current—may affect spawning and larval dispersal. Illegal trade across East Asia further exacerbates the problem, making conservation efforts more complex.

To address this crisis, Japanese researchers have worked to establish a complete aquaculture cycle for unagi. This involves breeding eels in captivity, raising their offspring to maturity, and creating self-sustaining populations. While these efforts are promising, they are still in the early stages and face significant logistical and financial hurdles.

Sustainable management will require international cooperation, stricter trade monitoring, and consumer awareness. Balancing Japan’s rich culinary tradition with environmental responsibility is key to ensuring that future generations can continue to enjoy unagi responsibly.

 

9. First-Time Tips: How to order and enjoy unagi like a local

9-1 How to order at an unagi restaurant

When you look at the menu at an unagi restaurant and see options like “松 (Pine),” “竹(Bamboo),” “梅 (Plum),” or “特上 (Special),” “上 (Premium),” “並 (Regular),” you might wonder what to order. In that case, choose based on how much unagi you want to eat. At most unagi restaurants, the price difference between unaju dishes mainly reflects the amount of kabayaki. However, some restaurants use different grades of eel rather than simply changing the portion size, which results in a higher price. These eels are typically wild-caught or specially cultivated brand varieties.

 

9-2 How to Use Sansho Pepper

Sansho pepper, an indispensable condiment for eel dishes, is Japan’s oldest spice. Sansho is a deciduous shrub of the citrus family native to Japan. The earliest documented reference to the relationship between eel and sansho, found in the “Ookusake ryorisho (大草家料理書),” dates back to the Muromachi period. This cookbook states that even the original form of kabayaki—grilled and chopped eel—was eaten with sansho miso.

Sansho’s pungent component, sanshool, stimulates the internal organs and aids digestion. Citronellal, an aromatic compound found in citrus plants including sansho, has calming, antispasmodic, and anti-anxiety effects. Diterpenes, the unique refreshing aroma component of sansho, stimulate and activate immune cells.

Three representative varieties of sansho cultivated in Japan are:

・Asakura Sansho (Hyogo Prefecture) — Thornless trees with large berries.
・Kogen Sansho (Gifu Prefecture) — Characterized by small berries and a bright, citrus-like aroma.
・Budo Sansho (Wakayama Prefecture) — Named for its grape-like clusters of berries.

The familiar powdered sansho is made by drying the skin of ripe sansho berries and grinding it into powder. However, the flesh of the berries, young shoots, leaves, and flowers are also used as aromatic seasonings.

Misansho (green, unripe fruit) pairs exceptionally well with eel, and eel simmered in sansho is commonly prepared throughout Japan.

Originally, sansho was used to mask the distinctive odor of eel. Nowadays, thanks to advances in aquaculture and cooking techniques, eel with a strong odor is rare. Therefore, it’s best not to immediately cover kabayaki with a large amount of sansho. Instead, savor the flavor with and without sansho.

 

Here’s how to sprinkle sansho pepper.

Lift the kabayaki, sprinkle your desired amount onto the rice or onto the exposed skin of the eel. Then, place the kabayaki back on the rice and wait about one minute before eating. This allows the aroma of the sansho pepper to gently follow the flavor of the eel. The rice will also carry a subtle hint of sansho pepper.

 

9-3 What to do with Kimosui (Eel Liver soup)

Here are some tips on how to best enjoy eel, as shared by eel chefs.

・The golden rule is to cook eel immediately after preparation. Once steamed and left to sit, eel quickly loses much of its flavor. So, allow time for proper preparation. Conversely, restaurants that make you wait after ordering are usually the trustworthy ones. (Authentic eel restaurants invariably take time to prepare your meal; waiting nearly an hour is common.)

・To avoid ruining the eel’s flavor, lightly sprinkle sansho pepper or place it in a corner of your bowl, adding only what you need. Traditionally, sansho was used to mask the eel’s earthy aroma. With farmed eel being the norm today, it’s often unnecessary.

・Sake pairs far better with eel than beer. Until the eel arrives, enjoy a drink with pickles that complement — rather than compete with — its delicate flavor.

・Even if it appears on the menu, avoid eating raw items like sashimi before your eel.

・Connoisseurs say eel is best eaten after September, not in summer. This applies only to wild-caught eel.

 

10. Conclusion: Why Unagi Is an Unforgettable Taste of Japan

Unagi is far more than just a delicacy—it embodies Japan’s deep respect for nature, craftsmanship, and seasonality. From the careful handling of live eels to the slow grilling process over charcoal, every step reflects centuries of culinary wisdom and devotion to harmony between flavor and texture.

Beyond its rich, smoky aroma and melt-in-the-mouth tenderness, unagi represents nourishment for both body and spirit. Eaten during midsummer to restore stamina, it has long been cherished as a food that connects people with the rhythm of the seasons. Regional variations—from Tokyo’s crisp-edged kabayaki to Kansai’s steamed-and-grilled style—reveal the diverse local identities that coexist within Japanese cuisine.

For travelers seeking to understand Japan through its cuisine, unagi offers an unforgettable experience—one that captures the heart of Japanese dining: respect, refinement, and the pursuit of harmony in every bite.

 

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