It’s nearly impossible to visit Germany and not eat Currywurst or Bratwurst, two ubiquitous sausage dishes. But regardless of the sausage’s fame, it seems that Germans can’t get enough of the döner kebab.

The nation of 82 million people consumes two million kebabs a day, according to Gürsel Ülber, spokesman for the Association of Turkish Döner Producers in Europe (ATDiD). Safe to say, the thinly sliced meat – cooked on a vertical spit, wrapped in pita or flatbread and topped with salad – overrules the sausage-duo as a preferred fast-food option; a prominent symbol of the cultural and economic influence of Turkish immigration on German society.

Kadir Nurman and Mehmet Aygun are the two men credited for bringing it to Berlin nearly 50 years ago. Both were part of the Gastarbeiter, a wave of guest workers brought in from Southern and Eastern Europe to boost West Germany’s post-war economy. And that they did, paving the way for a 200,000-strong workforce today.

Although there’s a lot of speculation as to the real story – with Aygun claiming he invented the snack a year before Nurman at his shop, Hasir, in 1971 – the ATDiD have formally given the honour to Nurman.

According to Ülber, Nurman sold Germany’s first döner kebab from his little stall across from Bahnhof Zoo in West Berlin back in 1972. What was traditionally grilled meat served with rice, salad and pita was transformed into a sandwich for hard-working and busy Germans to eat on the go, with both men claiming to have had the idea to put the meat inside the pita bread.

But irrespective of who first took the reins, both men set the foundation for what is today a €4bn trade in Germany, turning over a whopping 400 tonnes of meat a day and helping turn this much-loved street snack into a major staple of the German diet.

ATDiD reveals there are around 40,000 kebab shops across Germany, with Berlin leading the pack at 4,000, astonishingly more than Turkey’s most populous city, Istanbul, according to Visit Berlin. The German capital is closely followed by Munich, Frankfurt, Hamburg and Stuttgart.

There are around 40,000 kebab shops across Germany, with Berlin leading the pack at 4,000, astonishingly more than Turkey’s most populous city, Istanbul.

The street-food snack so beloved that in 2011 a clever bunch of German university students even created a solution to “kebab breath”: Papa Turk is a drink made from ginger, parsley, mint and lemon that is claimed to neutralise the garlicky aftertaste.

But why is it so popular?

“Because it tastes so good,” as Ülber simply put it. “In your hand, you hold all the good ingredients. You have good protein and salads.”

But it’s not just the taste, large portions or affordability – costing anywhere between €4.50 to €14. What seems to have struck a chord is the ease with which it can be adapted.

Nurman’s creation involved only beef. But over time and due to the availability of different meats, the döner took a new turn to include chicken, lamb and turkey as well as different breads and extra toppings. Every eatery adds its own touch.

“Variations like iskender kebab (thinly cut grilled lamb, tomato sauce, pita bread, melted sheep butter and yogurt), adana kebab (hand-minced meat kebab mounted on a wide iron skewer) and koefte (a meatball including parsley and mint) have also become popular with customers,” said Evren Demircan, co-owner of World of Kebap in Stuttgart.

But it is the classic beef döner that has got Demircan’s customers hooked. He sells about 500 a week. On weekends that doubles.

To find out what all the fuss was about, I headed to Germany, where I quickly realized how wrong I was to consider it just a late-night snack for hungover party-goers.

As I walked through the Frankfurt’s thriving financial district, I was amazed to see just how many choices there were for eating it, from fancy restaurants to little cafes fitted with beautiful Turkish décor. As the lunch-time rush kicked in on a busy Friday afternoon, locals, business people and tourists alike flocked to their nearest kebab eatery, happily waiting in long lines for a satisfying feed.

While some opted for mixed grilled plates or koefte, I went straight for the serious stuff: a large beef döner at Nazar Kebap Haus (Schäfergasse 38). As I gripped the pita and took my first bite, the chilli sauce and yoghurt-garlic dressing oozed from the bottom. It was amazingly fresh and flavoursome, with the combination of juicy meat, sauces and crunchy salad definitely living up to the hype.

It seemed to me that the Turks have been hugely successful in managing to keep the dish’s legacy alive while also adapting it to the competitive and ever-evolving food world. And as the largest ethnic group of non-German origin in the country (Berlin boasts the largest Turkish community outside Turkey) their döner kebab has served as an important vehicle in not only servicing the economy and satisfying locals, but has helped forge a bond between the two cultures.

For many Turkish immigrants, the döner has come to represent opportunity. And even after nearly five decades, with different generations keeping the döner legacy alive, the pioneers are never forgotten.

“Of course, we thank Kadir and Mehmet. Not only did they invent the kebab but they laid the groundwork for the whole industry and in turn many people’s livelihood,” Demircan said. “Many industries have profited from the döner trade.”

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