There's a reason Limfjord oysters are the best in the world

Johannes Christensen has spent half his life fishing for one of Denmark’s most prized raw ingredients. For the past 21 years he has pulled plump, meaty Limfjord oysters from the seabed.

“I still don’t really enjoy them raw. But if they are gratinated with cheese, butter and garlic, I can manage. Then the texture becomes almost like chicken meat,” says 41-year-old Christensen.

We are on board his fishing boat ‘Emma’, docked in the harbour of Fur, a small island within the Limfjord in northwestern Jutland. The Northwest of Denmark is the land of hard-working people muttering short sentences. It’s the land of huge windmills and flat, rugged coastal landscapes, where unrelenting winds fill the air with salt and sand.

Johannes Christensen has spent half his life fishing for one of Denmark’s most prized raw ingredients. For the past 21 years he has pulled plump, meaty Limfjord oysters from the seabed.

“I still don’t really enjoy them raw. But if they are gratinated with cheese, butter and garlic, I can manage. Then the texture becomes almost like chicken meat,” says 41-year-old Christensen.

We are on board his fishing boat ‘Emma’, docked in the harbour of Fur, a small island within the Limfjord in northwestern Jutland. The Northwest of Denmark is the land of hard-working people muttering short sentences. It’s the land of huge windmills and flat, rugged coastal landscapes, where unrelenting winds fill the air with salt and sand.

Christensen’s hunting grounds are home to the Limfjord oyster, arguably the rarest raw product found in all of Denmark. While Pacific oysters can be culled from other parts of the country’s coasts, the native flat Limfjord oyster only thrives in these waters, which bisects Jutland from the western inlet in Thyborøn.

The oyster is the truest example of Danish terroir – the very taste of a certain place. Although the flat European oyster (ostra edulis) is found from Morocco to France and the UK, it is here, at the northernmost edge of its habitat, that the cold water makes for slow growth and development of exceptional taste.

Still, the fisherman’s hesitation is warranted. These creatures are a bit of a handful, literally. They can reach the size of a human hand; a large, meaty mouthful that hits your tongue with an instant metallic hit, followed by rich, nutty sweetness and an aftertaste that lingers on the back of the tongue like a fine espresso.

Eric Vildgaard, owner of two-starred Restaurant Jordnær in the Copenhagen suburb Gentofte, is one the chefs coveting the Limfjord oyster. His refined meatless menu emphasizes local and sustainably caught seafood. Here, the Limfjord oyster reigns supreme.

“The Limfjord oyster is really something to be proud of. The oyster is a cultural heritage that should be kept alive, and I want to support that. You can go to a restaurant in France, and even here, where they have great oysters, you’ll often find Danish oysters as a showpiece on the menu. To me, what makes it unique is the very precise taste of the terroir. You have the intense minerality, the meatiness and the richness of taste, and yet it still comes off as refined and elegant. We serve it with pride.”

These properties have made the oyster sought after by chefs and gourmands all over Europe since commercialised oyster fishing began in the Limfjord in 1850. For hundreds of years, the Limfjord was closed off to the surrounding sea, and the water was brackish, but in 1825, a heavy storm flooded Agger Tange and re-opened the fjord. A few decades later, the oyster population thrived, creating a lucrative monopolised fishing trade in Nykøbing Mors, a quiet little town on Mors, a peninsula inside the fjord, since known as the shellfish capital of Denmark.

Today, roughly 15 million Limfjord oysters are exported annually, but they have been a beloved delicacy since long before that. Since around 5,000 BCE, the Limfjord oysters, along with other shellfish, were a vital part of the diet for the tribes settled on the banks of the fjord. Archaeologists uncovered a 140 metre long kitchen midden – essentially a stone age garbage dump – in which there was a massive amount of oyster shells, mussel shells and fish bones among the kitchen waste. This discovery allowed researchers to date and describe a whole new culture in the area, labelled as ‘Ertebølle culture’. The midden, amassed through 1,000 years of settlements, consisted of around 80 percent oyster shells.

Today, Nykøbing Mors still boasts both an oyster company and a shellfish research centre run by Denmark’s Technical University, dedicated to the conservation and the understanding of the area’s vital mussels and oysters. There is a logic behind that conservation approach. Although set quotas keep the population stable, the native oyster remains under pressure.

One threat to the oyster is a parasitic disease, bonamia ostreae, first discovered in 2015, which infects and kills the oyster population. Another is climate changes, causing fluctuating water temperatures in the shallow fjord, where hot summer months and harsh winters can cause hypoxia among the population. A third issue is other oysters.

The Pacific oyster (crassostrea gigas) – also known as gigas – is another species of oysters found along the Danish west coast. Native to Japan and South-East Asia, the Pacific oyster was introduced for aquaculture in Holland in the 1960s. Because of the region’s colder water temperatures, it was believed that the oyster wouldn’t be able to procreate. However, the gigas spread with gusto up the coast, and in 1999 the invasive species was discovered on the Danish west coast. They have since found their way into the Limfjord, where they grow in clusters at a much faster rate than the native oysters.

The Pacific oyster has a lighter flavour than its native cousin, less dense, with a refreshing cucumber-like taste. The invasive species are so close to the water’s edge that, in many places, you can walk out in waders and pick up as many as you can carry. Their tenacity, however, pose a threat to the original oyster population, explains Anita Hansen, a biologist at The DTU Shellfish Research Centre.

“In recent years, bonamia has been quite hard on the population. With the gigas, we are still unsure what their presence will mean in the long run. Five years ago, it was easy to find Limfjord oysters at the edge of the water. Today, that is very rare. Instead, you’re virtually tripping over the gigas, which can handle water temperature fluctuations way better than the native oyster. And when they spawn, one oyster can release up to 100 million larvae, whereas the native oyster releases one million at best,” explains Hansen.

She shows us around the centre’s brand new hatching facility, which has been established with the aim of breeding Limfjord oysters to be released into the wild in an attempt to strengthen the population.

A vital part of the stone-age diet 7,000 years ago, the oysters have since worked their way out of Danish kitchen culture. A decade ago, as much as 95 percent of the Danish oysters were shipped abroad to countries like France, Italy and Spain, where consumers are willing to pay a premium for top-notch shellfish. The Danes, however, didn’t care so much for delicacies growing on their doorstep, but in recent years, that has changed. This is, in part, thanks to oyster entrepreneur Kristian Borbjerggaard. Five years ago, he was fresh out of technical college, 18 years young and on a gap year with too much time on his hands. He decided to earn some money by trying his hand at selling local oysters to local restaurants.

Borbjerggaard noticed that at a time when Nordic cuisine was peaking and restaurants were proudly hailing local ingredients, the Limfjord oyster, a unique and pristine ingredient with a rich heritage and a highly praised gastronomic quality, was not receiving its due. Instead, it was being boxed and shipped off to Southern Europe.

“I was actually a bit dumbfounded when I learnt that so much of the oyster catch back then was exported. I read a survey which said that in all of 2013 the Danes only consumed 50,000 Limfjord oysters in total. I thought it was a great shame, and it was depressing to learn that we were exporting all the good stuff and importing oysters of sometimes lesser quality,” he says.

So, spending all of his childhood savings, he rented a space in a small fish farming plant, bought some oysters and set off going door to door, offering oysters to dumbfounded chefs, who claimed that guests would never pay extra to substitute the French or Dutch oysters with a native flat oyster. Borbjerggaard proved them wrong. Five years on, his company Venø Seafood (based on yet another small island in the northern part of the Limfjord), sold 45 tonnes of oysters, catering to both a private clientele and a majority of Denmark’s Michelin-starred restaurants.

Borbjerggaard shows us his recently expanded facilities, where crates upon crates of oysters are conditioned in four large concrete basins, each containing up to 90,000 specimens of both Limfjord and gigas oysters wallowing in highly purified fjord water. With Limfjord oysters as his main product, Borbjerggaard is less worried about the intrusive gigas.

“Some people regard them as a big problem. But generally, our fishermen aren’t too worried about them. They are mostly found on shallow waters, whereas the Limfjord oyster is found at greater depths.”

He has decided to do what he can to rid the waters of the intruders, all while making a buck at the same time. Since the gigas are mostly found in shallow waters close to land, they cannot be fished with fishing vessels. Intead, he has employed divers to handpick the gigas, which might be a pest, but are still undeniably tasty.

“The quality of these oysters is great. The taste of the Limfjord oyster is too intense for some people, whereas the gigas is more of a ‘beginner’s oyster’. And even though they must be collected by hand, they still end up cheaper than the native oysters. This means that I can offer my clients a local product that can rival the imported ones, both in terms of quality, taste and price.”

Back on board the boat ‘Emma’, Johannes Christensen is also positive about the future for the native oyster. “Sure, the amount of gigas has been on the rise, but for the past few years they seem to be posing less of an issue,” he says.

To him, the biggest problem is not the gigas, but rather the tight fishing regulations in the protected areas of the Limfjord. The protection regulations allow the fishermen’s vessels to run only in designated ‘squares’ in specific areas. From Christensen's perspective, this approach is depleting those specific areas whereas spreading out the oyster fishing would be much gentler.

“Right now, we are creating deserts on the seabed, because the boats are fishing the same spots over and over, and that is killing the spawn. I am a bit frustrated about this. This sort of bureaucracy is by far the worst part about the job. The reality is often different from what is printed on paper. It is draining both the fishermen and the seabed.”

The balance between using natural resources and protecting them is by no means an easy task. But if care is taken, the heritage of these unique oysters can hopefully live on for generations to come.