Every year, the Egyptian Ministry of Health issues a warning: stay away from feseekh, the country’s traditionally salty – and smelly – fermented mullet fish that dates back thousands of years. If not prepared properly, the Ministry has cautioned, the spoiled fish can lead to botulism poisoning and, in rare cases, death.

At Shaheen for Salted Fish and Caviar, Cairo’s famed fish shop specialising in the putrid delicacy, the Ministry’s warnings have proved to be a blessing in disguise.

“We consider it positive advertising,” laughed Sabry Shaheen of the family-run shop. “This makes our traffic increase.”

About 100 years ago, the family’s patriarch, Mohamed Shaheen, came to Cairo from Minya, a city along the Nile River in Upper Egypt, and started selling feseekh. In 1912, he set up a self-named fish shop in the historical Bab al Khalq area of Islamic Cairo, and was the first fasakhani – one who specialises in the fermented fish – in the capital. From there, he grew the family franchise. Now, the main shop, opened in 1955 in the more centrally-located Bab el-Louq area of downtown Cairo, sells other specialties like caviar, herring-like ringa, and meluha (another fermented, Egyptian fish), in addition to feseekh.

Around Cairo, there are several feseekh-selling shops calling themselves Shaheen, but only two are officially part of the Shaheen-family franchise; the other shops try to capitalise on the name’s fame, Shaheen said. And it definitely pays to buy the fish from a proper source: in 1991, the worst year on record, 18 people died from eating feseekh, according to the Ministry of Health. But not from Shaheen’s shops, I was assured when I stopped in this past January: his shops are certified and he’s never had a complaint from a customer or the Ministry of Health.

That’s why Emad Iskander only buys feseekh from Shaheen. And he keeps coming back again and again for it – even though, like many Egyptians, he also kind of hates it.

“I don’t like it,” Iskander admitted. “But I eat it.”

Egyptians, he explained, have a ‘personal schizophrenia’ with the fish, which is served with brown baladi bread, a little oil, lemon and onion to soften the bite.

“Some Egyptians say they don’t eat it because it’s masry [Egyptian] and considered bee’a [low-class],” Iskander explained. “They want to act more like foreigners. But they keep eating it anyway.”

Unlike some other Egyptian delicacies, you won’t find the stinky dish in restaurants, but Shaheen’s customers continue to identify eating feseekh as part of their Egyptian culture. In fact, feseekh dates back to Pharaonic times, when each spring the receding Nile River left behind trails of rotting fish. Even today, Egyptians traditionally eat feseekh during the spring Shem el-Nissim holiday (which fittingly translates as ‘smell the breeze’) to commemorate this part of their heritage.

Shaheen is busiest the month before Shem el-Nissim, when Egyptians begin to buy the fish in bulk. But many in Cairo eat feseekh and ringa – a more palatable and less controversy-inducing herring – on other holidays, for special treats, and on Fridays, the main Muslim prayer day and start of the weekend. So, the fermenting never stops.

The recipe itself is seemingly simple: the mullet, also called borai fish, is dried in the sun and then placed in large wooden vats filled with the right ratio of salty water for 45 days The key to success, Shaheen said, is in knowing all the subtle fishy rules. While the fish technically remains raw, the salt ‘cooks’ it, in theory preventing any rotting. The end result is a seemingly inconspicuous fish on the outside with a grey-tinged, gooey centre that reeks with a particular all-encompassing stench. If not prepared with enough salt or if there’s already dead fish floating in the water, botulism bacteria, which thrive in anaerobic environments, can fester and cause nausea, paralysis, or in rare cases, worse.

A Coptic Christian, Iskander and his family buy and eat feseekh and ringa on Easter and certain fasting days, during which consumption of animal products is limited. His wife loves the fish for its sense-numbing saltiness. But Iskander does not love the distinctly stinky smell that lingers in the house for days, nor the upset stomach that sometimes follows. It’s a hassle to eat, he lamented. But Iskander also wouldn’t have it any other way – to him, and to many others, these special moments aren’t the same without feseekh.

That’s why, despite the inevitable changing tastes of changing times, Shaheen isn’t worried about the fish’s long-term future, even though, these days, Egyptians of all classes are cutting back a bit due to tough economic times. Egypt’s economy has been unsteady since the 2011 Revolution, and took a major hit in November 2016 when the government floated the Egyptian pound in preparation for an International Monetary Fund loan. Suddenly, prices on goods began rising with seemingly no rhyme and reason.

Customers who used to buy 3kg of feseekh (about one kilo a fish) now buy one or two, Shaheen said. In January, he sold a kilo of feseekh for 120 Egyptian pounds and ringa for 50 – the former nearly doubled from the price seven years ago.

A smaller segment of Shaheen customers are doing it themselves, like Ahmed (who declined to give his surname), whose wife started making faseekh at home three years ago after seeing it on a cooking show and searching the internet for tips.

Making the feseekh takes sabr [patience],” Ahmed explained. They let the fish soak in salty water for more than a month and shake it once a week. “But homemade food is best,” he insisted.

The timeless desire for a taste of home cuisine is what brought Ibrahim Hamed Attia to Shaheen the afternoon I was there. He was flying that night to visit Egyptian friends working in Kuwait – and they had requested he bring them the shop’s feseekh for a treat. When I asked whether he worried about the fish spoiling on the trip, the cashier at Shaheen cut in, suggesting, “Tell them to put it on ice in the plane!”

Attia shrugged. It wasn’t anything the feseekh couldn’t handle.

Culinary Roots is a series from BBC Travel connecting to the rare and local foods woven into a place’s heritage.

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