There Are Too Many Jellyfish in the Mediterranean. Why Not Eat Them?

Italian chefs are trying to adapt their cuisine for a world with fewer fish.

A glowing jellyfish
DeAgostini / Getty

This article was originally published in Hakai Magazine.

On a snowy January morning in 2022, I walked into Duo, an exclusive little restaurant in the heart of the southern Italian town of Lecce, carrying a polystyrene box filled with two frozen, plate-size jellyfish. With me was Antonella Leone, a senior researcher at the Italian National Research Council’s Institute of Sciences of Food Production, who held an authorization letter for Chef Fabiano Viva to legally handle the sea creatures. Viva awaited us at the restaurant’s entrance, greeted us with a hearty handshake, and took the cooler. Within minutes, his assistant was defrosting the jellyfish under the tap. Viva laced up his white apron, filled a pot with water, and ignited the stove.

Leone is part of a small group of scientists who have been studying Mediterranean jellyfish for the past 12 years. For the past seven, they have involved chefs, testing ways to get the general public interested in eating the marine invertebrate.

“The idea of eating a jellyfish never crossed our minds, because we would only see one every once in a while,” Leone explained. However, as several species of local and alien jellyfish became abundant—such as in 2014, when a jellyfish bloom saw 400 tonnes of the barrel jellyfish per square kilometer carpeting the massive Gulf of Taranto—Leone wondered what they could do with them.

But persuading Italians to eat jellyfish is like enticing them to try pineapple on pizza—not a simple task. Southern Italians eat octopus, sea urchin, and other sea creatures, but jellyfish are largely ignored. Selling jellyfish for human consumption is prohibited in the European Union, as regulators still do not consider the sea creature a safe, marketable food due to historical lack of interest in them as a food source—which is why Leone arrived at Duo with a permission letter in hand.

Safety concerns around jellyfish don’t seem to be a problem in China, where jellyfish have been on the menu for almost two millennia. (A favorite is an appetizer of chilled jellyfish seasoned with dark vinegar, sugar, soy sauce, chicken-stock powder, and sesame oil.) A recent estimate found that 19 countries harvest up to 1 million tonnes of the gelatinous sea dweller, contributing to a global industry worth about $160 million.

Partnering with forward-looking chefs such as Viva, Leone and her team began researching in 2015 ways to make jellyfish tasty and safe for Mediterranean menus. As ocean fish stocks continue to deplete at alarming rates, while jellyfish seem to thrive, more and more people are asking if eating jellyfish will effectively mitigate the jellyfish problem, and if they will become a sustainable and safe source of food. But can jellyfish become a food for all?

Jellyfish are in a broad group of aquatic animals that marine biologists refer to as “gelatinous zooplankton.” Some, like the highly venomous Irukandji box jellyfish, mainly found off the coast of Australia, can have a bell as small as a cereal flake; others, like the enormous lion’s mane jellyfish, have tentacles up to 36 meters long. Jellyfish are an important part of marine ecosystems and serve as meals for 124 fish species and 34 other animals, such as the leatherback sea turtle.

But all is not well in the jellyfish world. Since the turn of this century, scientists have witnessed a worrying increase in jellyfish populations in various parts of the world. According to Lucas Brotz, a researcher who has long studied jellyfish at the Institute for the Oceans and Fisheries at the University of British Columbia, it’s not easy to understand the reasons behind the phenomenon.

“Not all jellyfish are increasing in all places, but we do see a sort of sustained major increase in many areas around the world,” Brotz says. And myriad reasons could be driving this change, among them alien jellyfish species being introduced into new areas and range expansion as climate change and warming waters favor some species over others.

The jellyfish increase is being felt particularly acutely in places such as the Mediterranean Sea and along the coast of Japan. Hordes of jellyfish have damaged fish farms, clogged power plants, capsized fishing boats as they’ve weighed down nets, and upended tourism by making waters unsafe for swimming. And their presence can affect creatures they share the sea with too.

“Imagine [something the size of] the biggest oil tanker in the world traveling along the Mediterranean coasts to Israel, consuming all the plankton,” says Stefano Piraino, Leone’s husband and a marine biologist and jellyfish expert at the University of Salento, in Lecce, explaining how massive blooms of jellyfish can hog all the plankton that other planktivores need.

Seeing the new availability of jellyfish in the Mediterranean, Piraino joined Leone in her quest to find possible culinary uses for jellyfish.

Back at Duo, Viva slipped on latex gloves and carefully lifted the Rhizostoma pulmo jellyfish from below the running tap. They were still a bit frozen—quite unlike the dried jellyfish often used in Eastern cuisine, which must be rehydrated before use. Viva put the jellies into a pot of boiling water and started stirring.

When Leone first began studying how jellyfish could be used for food or food ingredients—and how they could be preserved for later use—she stumbled upon one main problem. The primary method of preserving jellyfish, as perfected in Asia, was to dehydrate them using the chemical compound alum. But, she said, consuming aluminum can be toxic, and alum-treated jellyfish generally don’t meet the European Food Safety Authority’s standards. So Leone and her colleagues set out to devise a new and nontoxic way of desiccating edible jellyfish.

Her team overcame the drying challenge by using calcium salts instead of alum and went on to experiment with dried, fresh, and frozen jellies, turning them into mousse, meringue, seasonings, and thickeners.

The magic of turning gelatinous macrozooplankton into food and food products happens in Leone’s lab at the Institute of Sciences of Food Production, where she and her team of seven run their experiments. A long steel testing table, with two shelves of transparent jars and scales at its center, separates the expansive room. Inside an industrial fridge rest racks of test tubes containing jellyfish extracts.

But it is one thing to do research in a lab and another to convince Italians to consider replacing fish with jellyfish in soup. According to a 2020 study led by Luisa Torri, a professor of food science and technology at the University of Gastronomic Sciences of Pollenzo, there might be some hope for acceptance. The study surveyed 1,445 people on their attitude toward the idea of consuming jellyfish, taking into consideration traits such as age, behavioral habits, and mouthfeel. According to the results, young, well-traveled people with higher education levels and sensitivity to the environment are more likely to eat jellyfish.

I fit that category, so when Viva invited me to take a whiff of the white foam bubbling rapidly on the stove, I tried to keep an open mind.

I closed my eyes and breathed deeply. “It smells like oysters,” I told him.

“You need to disconnect your brain from what you know,” Viva replied. “You need to detach yourself from the food in your memory.”

Is the key to accepting an unusual food making new food memories? If that’s the case, we’ll need to find a way to get jellyfish from the sea to dinner tables.

In addition to helping to deal with future seas full of jellyfish, fishing for these creatures has been touted as a way to help small-scale European fishers, who are struggling with low fish stocks.

“A source of income? That would be great!” says Rocco Cazzato, a sixth-generation small-scale fisher from Tricase Porto, at the idea of fishing jellyfish. “But I would never eat them, not even if it’s the last thing left in the world to eat.”

Cazzato recounts the pain of pulling in fishing nets crowded with jellyfish that he could not sell. He says that if jellyfish were in demand locally, like the commonly consumed scorpionfish, those jellyfish in the net would help small fishers like him make ends meet.

Although Leone is working to fill the information void, knowing which jellyfish are edible and safe for consumption is still a question few researchers are tasked with answering. According to Brotz, while many different jellyfish types are increasing worldwide, only a handful of them are preferred for human consumption. And just because they seem to be more abundant doesn’t mean that fishing them will be a panacea. The title of a 2016 paper co-written by Brotz says it all: “We should not assume that fishing jellyfish will solve our jellyfish problem.”

The paper advises caution: Jellyfish are understudied, and the effects of removing them from the ecosystem, even when they are in excess, are unknown and potentially negative. Some jellyfish, for instance, act as nurseries for juvenile fish, and jellyfish can be both predator and prey in food chains.

Silvestro Greco, a marine biologist and the research director at the Anton Dohrn Zoological Station, echoes the concern that fishing isn’t necessarily the way to combat jellyfish blooms. He fears that once industrial jellyfish extraction begins, quick depletion might have unexpected consequences for local marine environments. In the early 2000s, for instance, a portion of the fishing fleet in the Gulf of California, Mexico, diverted its efforts to harvesting jellyfish. Fishers and processing-plant workers quickly profited from the new market but overfished the resource, leading to the rapid depletion of jellyfish.

Still, some fishers are poised to launch if a fishery opens—there is already curiosity from Asia about fishing jellyfish in the Mediterranean. But even with interest from fishers, if there’s no market, there’s no point.

According to Leone, getting jellyfish to the masses requires an entrepreneur willing to invest the several thousand euros needed to request that the European Food Safety Authority accept jellyfish as edible food for sale, allowing them to be legally sold in fish markets and restaurants.

Leone believes that she and her team have gathered the scientific research to support such an application to EFSA, and that some entrepreneurs have shown interest. It’s only a matter of time before some species of jellyfish make the list of approved European foods, she said, and she’s keen to broker the divide among fishers, markets, and chefs.

Creating this market could help artisanal fishers, the ones most affected by jellyfish blooms, Leone said: “They come back with nets full of jellyfish and three fish inside. If jellyfish would become accepted edible food, they could sell it as sea products like others.”

Leone first targeted curious chefs—ones without preconceptions who were eager to accept a challenge—in 2015, and they became important team members. Leone and her team were part of the EU-funded GoJelly project, which looked into new uses for jellyfish—including in fertilizers, cosmetics, and nutraceuticals, and for snaring microplastics. Membership meant that Leone could regularly bring Viva and other chefs jellyfish to experiment with in their kitchens and find ways to make the sea creature appetizing. Over the years, Viva has tried the jellyfish pickled and dehydrated like chips, and as an ingredient in soups and pasta sauces.

The most significant difficulty encountered by Pasquale Palamaro, the executive chef of the Michelin-star restaurant Indaco, on the island of Ischia, was the drop in weight as the jellyfish cooked.

Jellyfish are 95 percent water and a small percentage of proteins, and when the animal dies, it loses much of that water. To avoid this, Palamaro believes they have to be consumed fresh within a few hours of harvest, or stored safely frozen or preserved with the calcium-salt technique that Leone developed.

Palamaro boils the Pelagia jellyfish from the Mediterranean for one minute, marinates it in citruses for an hour, and then seasons it with pumpkin-seed oil before serving it with quinoa. Gennaro Esposito, the chef of the Michelin-star restaurant Torre del Saracino, in Vico Equense, prefers to pair the jellyfish with marinated cucumbers, chili kefir, and lettuce paste. Leone has collected the more successful recipes of these chefs and others in the freely available European Jellyfish Cookbook.

But not all chefs are convinced of the jellyfish’s culinary potential. In 2017, Greco, who is also a food scientist and an avid cook, fried 50 kilograms of Pelagia jellyfish at the Slow Fish conference in Genoa, Italy, to create awareness about the rapid rise in jellyfish numbers in the Mediterranean.

“It was a success,” Greco says, “but because they were fried. Everything fried is good.”

He believes jellyfish don’t have an interesting texture and don’t make a compelling case for culinary indulgence. All in all, he doesn’t believe that jellyfish will be quickly adopted by cuisines that don’t traditionally use them.

But according to Leone, jellyfish today are in the same situation as tomatoes in the 16th century. Tomatoes, now a key ingredient in traditional Mediterranean cuisine, were unknown before being brought over from the Americas around the 1550s. At first, they were thought to be toxic and unhealthy. However, possibly thanks to forward-looking cooks or simply because of necessity, tomatoes began appearing on pizzas and in parmigiana and pasta sauce, ultimately becoming part of the Mediterranean diet.

Whether jellyfish will take a similar trajectory and become accepted in Western markets is hard to say, but many of our favored seafoods are declining or have already collapsed, Brotz explains: “We may get to a point where there is no other seafood available.”

Back in the kitchen at Duo, Viva turned one of the two jellyfish into a soup, adding tomato sauce, olive oil, a garlic clove, and a pinch of parsley. He offered me a serving.

I spotted the turgid tentacles and part of the cap floating in the orange liquid, and my stomach turned. The first spoonful of broth went down quickly. It tasted like a delicious—and fishy—tomato soup. Then I searched for a piece of the jellyfish. I hesitated, then slurped it up.

It felt like taking a gulp of the sea itself, the flavor of the jellyfish unfurling in my mouth with the strength of a tsunami. The texture reminded me of calamari or a piece of fat from a cooked steak. As I chewed, trying to repress my instinctive disgust, I thought of cooked tripe. I swallowed.

I looked at Viva and said, honestly, “It tastes like the sea!” He smiled, agreeing.

As I took a few more polite spoonfuls, the words of Esposito, the chef of Torre del Saracino, came to mind. He points out that jellyfish carry a stigma, but that the instinct to avoid them can be unlearned. Through cuisine, “we transform a fear and a dread into a taste, which is better,” he says.

I reflect that my hesitancy might be a result of cultural heritage—this food is as unfamiliar to me as a tomato was to my ancestors more than 500 years ago—as Viva prepares the other jellyfish. He coats it in flour and deep-fries it in vegetable oil.

This time, it is crunchy and crispy—like a French fry. And of course, it tastes great.