BY THE OPTIMIST DAILY EDITORIAL TEAM

Water lentils, a protein-packed and environmentally friendly plant, have officially been approved as a vegetable in Europe, offering a promising contribution to the protein transition and global food security. However, for this tiny but mighty plant to make a real impact, both food producers and consumers must first embrace it.

From duckweed to dinner plate

Most people might recognize water lentils as duckweed—the small, green plants that float and multiply rapidly in stagnant water. While commonly consumed in Thailand and other parts of Asia, they have yet to gain popularity in the West, despite being referenced as early as 1644 in a Dutch herbal book as ‘Water Linsen oft Enden Groen’ (Water Lentils or Duckweed).

That might be about to change.

Senior researcher Dr. Ingrid van der Meer of Wageningen Plant Research first became interested in water lentils a decade ago. “They have a number of biological processes that differ from those of other plants,” she explained. “From a scientific point of view, water lentils are very intriguing.” Over time, her fascination deepened. “They grow quickly, are suitable for contained cultivation, and their dry weight contains massive amounts of protein. I thought: why don’t we eat this?”

A sustainability powerhouse

In many ways, water lentils are the ideal vegetable for a more sustainable future. “They are an exceptionally sustainable vegetable,” said Van der Meer. “They are cultivated on water and don’t need many nutrients. Of course, water is a precious commodity, but in a simple greenhouse or vertical farm, growers can use it very efficiently.”

Unlike traditional crops, water lentils require no farmland, making them ideal for indoor farming—even in urban environments. Additionally, they grow exponentially, much like yeast, doubling every three days. With proper cultivation, they can yield over six times more protein per hectare than soy, according to calculations by Wageningen University & Research (WUR). And the best part? They require no pesticides.

Packed with nutrition and taste

With increasing calls to adopt plant-based diets for both health and environmental reasons, water lentils are well-positioned to play a key role. Not only are they rich in vitamins, minerals, and antioxidants, but they also contain a perfect balance of essential amino acids, making them a highly nutritious leafy green.

But how do they taste? According to WUR studies, taste panels gave water lentils high marks. “They have a plant-like, slightly nutty flavor and have a nice bite despite their size,” researchers found. In various test dishes—including soup, stew, ravioli, and pesto—panel members responded positively, encouraging chefs to explore their culinary potential.

Overcoming regulatory roadblocks

Despite their potential, water lentils faced significant legal hurdles before gaining approval in the European Union. The European Food Safety Authority (EFSA) classified them as a ‘novel food,’ meaning they required extensive scientific research and regulatory approval before hitting the market.

“It takes immense amounts of time and money to submit a novel food request,” Van der Meer noted. Determined to see water lentils widely accepted, she and her colleagues at Wageningen Research compiled a comprehensive dossier proving their safety. With support from the Wellcome Trust in London and the Goeie Grutten foundation, the researchers successfully met EFSA’s stringent requirements, including demonstrating that water lentils could be cultivated with manganese levels comparable to spinach.

Their persistence paid off. In 2021, EFSA approved the consumption of Wolffia, the type of water lentil traditionally eaten in Thailand, under more relaxed guidelines. Now, with the recent approval of the Lemna variety, European consumers have a new sustainable food option.

Bringing water lentils to market

With regulatory barriers cleared, the next challenge is commercial production. Currently, water lentils are not cultivated at scale within the EU. However, other countries are already taking the lead. In Israel, they are marketed as ‘green caviar,’ while a U.S.-based start-up founded by two Dutch entrepreneurs is working on extracting protein from the plant.

Since 2022, Wageningen University has been coordinating efforts to bring together industry players to explore sustainable production methods such as vertical farming. The goal is to integrate water lentils into mainstream food products—whether fresh, frozen, or as an ingredient in pasta, cheese, smoothies, or plant-based meat substitutes.

Consumer acceptance: the final hurdle

While researchers and food industry leaders work on supply, they are also looking at demand. “We need to keep the consumer in mind,” Van der Meer emphasized. “We won’t continue the project if people don’t want to eat water lentils.”

To gauge public interest, Wageningen Food & Biobased Research conducted extensive consumer studies. Over 1,000 participants were surveyed based on background information and product images, while others took part in taste tests. Initial hesitation gave way to approval—after just a couple of days, participants found water lentils as enjoyable as spinach. In fact, some even preferred water lentil soup to its spinach-based counterpart.

Yet, the biggest challenge remains: getting food companies to take the leap. “It’s a chicken and egg situation,” Van der Meer admitted. “Are food companies waiting for interested consumers, or can consumers only develop a taste for this product once it’s available?”

One thing is clear: if water lentils gain recognition as quickly as they grow, they might soon become a staple on European plates.