Exploring deep eutectic solvents and enzyme-based hydrolysis for hemp seed flour valorization

This study explores the valorization of hemp seed cake flour (HSCF) through a combined delignification and enzymatic hydrolysis approach aimed at improving its nutritional and technological properties for food applications. HSCF was pretreated with a choline chloride–glycerol deep eutectic solvent (DES) under different temperatures and biomass-to-solvent ratios. The optimal pretreatment conditions (120 °C, 1:8 biomass/DES) achieved a 32.6 % reduction in lignin while maintaining high biomass recovery (>85 %). Subsequent enzymatic hydrolysis reduced by 11,9 % the total insoluble fibre and led to the release of xylooligosaccharides (XOS) with potential prebiotic activity. Structural analyses (FTIR, XRD) confirmed the selective disruption of the lignin–hemicellulose–cellulose complex and improved crystallinity of cellulose. These results demonstrate that DES-assisted enzymatic hydrolysis provides an effective and sustainable route for upgrading hemp seed cake flour, generating functional flours with improved compositional and structural attributes suitable for the development of plant-based food products. • A biomass/DES ratio of 1:8 and 120 °C is the optimal condition for delignification. • DES pretreatment and enzymatic hydrolysis reduces the fiber content. • An increase in concentration and bioavailability of valuable nutrients was recorded.