HEUKSAN ISLAND, South Korea — South Korea has a generous list of foods some find hard to swallow, among them boiled silkworm pupae and live baby octopuses, which have been known to attach their suction cups to the roofs of diners’ mouths in what appear to be desperate bids to escape.

But fermented skate from this southern island tops them all. By far South Korea’s smelliest food, the fish, called hongeo, is described by lovers and detractors alike as releasing odors reminiscent of an outhouse. Served most often as chewy pink slabs of sashimi, hongeo is prized by enthusiasts for the ammonia fumes it releases, sometimes so strong they cause people’s mouths to peel.

“I used to think that people could not possibly eat this stuff unless they were crazy,” said Park Jae-hee, a 48-year-old marketing executive. “But like smelly blue cheese, it has no replacement once you fall in love with it.”

It is easy, of course, to poke fun at other nations’ cuisines: Consider Europeans’ wrinkled noses at the American penchant for slathering ketchup on everything from fries to scrambled eggs. But some South Koreans who are otherwise fiercely proud of their fiery, often odoriferous foods, like kimchi, admit to being repelled by hongeo and baffled by its rising popularity.