Swedish researchers see green biorefineries turning leys into protein and more

Researchers at Chalmers University of Technology have explored green biorefineries that process grass and clover into protein feed and other products, potentially reducing reliance on imported soy. The approach also improves soil quality when leys are introduced into cereal-dominated crop rotations. The findings appear in the journal GCB Bioenergy.

The Chalmers research builds on Danish pilot facilities that first demonstrated protein extraction from fresh grass. The Swedish team recognized this as a pathway to address two linked problems: the lack of market demand for ley biomass in cereal-dominated regions, and Europe's heavy reliance on imported soy protein, which carries environmental drawbacks including pesticide use and nutrient cycle disruption.

The biorefinery process separates protein from freshly harvested grass and clover, leaving fiber-rich residues with multiple potential applications beyond biogas, including biochar production, textile manufacturing, and carbon capture where CO₂ could be stored underground or substituted for fossil-derived carbon in industrial processes. Researchers emphasize that integrating leys into cereal rotations improves soil fertility and biodiversity conditions across agricultural landscapes.