Investigating a sustainable “superfood”

Pioneer Fellows Cyrill Hess and Melanie Binggeli want to market duckweed as a healthy food that’s good for the environment.

Best described as light green, with a taste reminiscent of bean sprouts and a pleasantly grainy texture, Wolffia is one of five genera of a plant commonly known as duckweed or “water lentils”. It is also the most easily digestible, as Cyrill Hess explains at an impromptu tasting in a basement-​level environmental chamber at ETH Zurich’s Department of Environmental Systems Science. Just before, Hess had used a sieve to skim the Wolffia off the water in a wooden basin in front of the tasters. The grass-​green carpet floats atop an aqueous nutrient solution that is continually cleaned by a pump. In the environmental chamber, scientists can precisely control temperature, humidity and lighting conditions.

Hess started cultivating the Wolffia two weeks ago on a water surface measuring about five square meters. On a good day, he skims off 1.5 kilogrammes of this “green caviar” – that’s what he calls the product that his start-​up, LemnaPro, is working on.

He discovered his enthusiasm for alternative and sustainable foods in Achim Walter’s lectures on alternative crops. Walter, Professor of Crop Science at ETH, wants to help build a sustainable world food system through research, new technologies and alternative crops. Walter helped Hess obtain a position as a guest researcher so he could use the lab and environmental chambers to further refine his idea.

ETH Zurich News