Algae protein-rich – with spillage from herring

Algae can eventually replace soybeans as a more environmentally friendly protein crop. In Bohuslän, green algae are grown for research purposes – and fertilized with wastewater from the herring and shrimp industry, reports SVT Nyheter.

In Sweden’s saltiest waters, in the Kosterfjord outside Bohuslän, researchers grow algae with the goal of making them as protein-rich as possible. The solution: to let them grow in residual water from various processes in the food industry.

“We have seen that we can increase the protein content more than three times in the waste water. It is noticeable already after 14 days. Then we will reach 30-35 percent at our best,” Kristoffer Stedt, a doctoral student in marine sciences at the University of Gothenburg, told SVT.

The waste water comes from, among other things, shrimp boils and herring pickles, whose residual products are rich in nutrients. The hope is that the algae, in the long run, will be able to challenge common protein crops such as pea and soybean, where the cultivation of the latter sometimes leads to the devastation of rainforests.

– Growing algae is the future. They grow in water and we don’t need to use any ecosystems on land that are often overexploited. Algae do not need manure, they grow from sunshine, they absorb nutrients from the water and also purify the sea, says Sophie Steinhagen, who is working on the project.

The harvested algae are dried and ground down into a powder that can be used in food production.

Än kan dock algen inte kallas en proteingröda på samma sätt som sojabönan, vars proteinhalt ligger på mellan 40 och 50 procent, säger Ingrid Undeland, professor i livsmedelsvetenskap vid Chalmers.

She believes the algae protein will be available on a large scale within four to five years.