On the southwestern tip of the Korean Peninsula, laid out across ferry-filled harbors and rolling hillsides, is a vibrant port city called Mokpo.

Famous for its Japanese colonial architecture and for being the jumping-off point to scenic islands like Heuksan and Jeju— the "Hawaii of Korea" — Mokpo is also known for its fishing industry and its local seafood delicacy: hongeo.

Most South Koreans shake their head at eating hongeo. This fermented skate dish has a sharp, pungent aroma one might describe it as a heady mix of public toilet and wet laundry left untended for days – and a hard-to-swallow texture of chewy flesh and crunchy cartilage. But in Mokpo, it is a beloved meal and a vital part of the local economy.

Trawling for skate, the key ingredient in hongeo, is big business in Mokpo's bustling harbor. During peak season — between November and March --fishermen haul the prized catch from their trawlers by the hundreds and deliver it to restaurants.

Once in the hands of regional chefs, this drabby-colored and bottom-dwelling fish undergoes a most curious form of fermentation.

"The skate doesn't pee like other animals," explains Kim Mal-shim, owner of Deok Inn Jip, a local hongeo restaurant in operation for 33 years. "It releases urine through its skin."

After about a month of incubating in its own urine, the hongeo – smelling thoroughly of ammonia — is served as a platter of sashimi in a presentation known as samhap, which translates as "harmonious trinity." This combination consists of hongeo, bossam (boiled pork belly) and old kimchi, a combination known to counter the wretched odor — if not mask the flavor altogether.

While hongeo is undeniably an acquired taste, for residents of Mokpo, it is also a cultural touchstone.

"It is an essential serving at important dinners," says Kim Kyung-sun at Mokpo's tourist information center. "So important that if [it is] left out of the table, then one feels depressed and cheated."

This perhaps could explain why 11,000 tons of hongeo are consumed annually in South Korea. Then again, that number looks paltry when compared with the 2 million tons of kimchi that end up on dinner tables nationwide.

How did this unusual dish gain its exalted status in Mokpo? The answer traces back to the mid-14th century. Back when Japanese pirates patrolled the South Seas, Korea's Gongmin forced the residents of Heuksan Island to move up the Yeongsan River. While heading inland and taking their fare with them, these settlers discovered that all their fish would go bad — except for the skate. Left to ferment in its own urine, the fish was naturally preserved and seemingly palatable.

From that moment on, hongeo thrived and became an esoteric edible at royal galas for the wealthy yangban ruling elite. Today, it is considered a regional specialty in South Korea's southwest provinces of North and South Jeolla.

Professor Jin-Soo Kim, from the Department of Seafood and Aquaculture Science at South Korea's Gyeongsang National University, has spent years studying hongeo (the Korean word for both the skate and the dish). Like many fish, hongeo is rich in nutrients like omega-3 fatty acids and taurine, "which is important for growth and development," he notes.

But many devotees attribute other alleged health benefits to this unusual dish – for instance, that it can improve digestion and help alleviate hangovers.

Mokpo's hongeo fishermen have had some unwelcome competition in recent years from skate imported from Chile. Given hongeo's importance to Mokpo's economy, it's not surprising that local restaurateurs disparage the quality of this Chilean variant and how it is preservedsomething Korean chefs say is an art form in and of itself.

"The hongeo from Heuksando Island live in colder water, which means that they are more nutritious, chewy and delicious," asserts Park Hyeong-dong, who owns and runs Heuksan, a hongeo restaurant in the heart of Busan, South Korea's second-largest city, located in the southern part of the country.

Adds Kim Mal-shim, owner of Deok Inn Jip: "Imported hongeo also contains a lot of preservatives. But the kind from Heuksan Island is fresher, so Chilean hongeo cannot be sold at my restaurant."

Many men from older generations eat hongeo as a form of asserting their masculinity or, as they claim, to enhance their virility (yet another hongeo health claim). But eating hongeo is now becoming a trend among the younger generations, too, says Sue Ahn, a prominent food journalist based in Seoul, whose main goal is to promote Korean food to the world.

However daunting it may be to give hongeo a try, there is certainly a proper way to eat it, Ahn says.

"You have to pick up the hongeo, breathe through your mouth, then out your nose. After that, you eat it," she explains. Fans insist that once you've tried this challenging dish four times, you'll get hooked by "that minty feeling in the back of your throat [that] many say is addictive," she says.

Ahn says it's a pleasant — yet short-lived — reward to hongeo's "ammonia-hair-dye, bone mush" taste.

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