Valorization of Rapeseed Meal: Production, Fractionation, and Utilization Routes

Rapeseed meal is a major by-product of rapeseed oil production and contains proteins, structural carbohydrates, and bioactive compounds with potential uses in feed, food ingredients, functional materials, and thermochemical products. However, broader valorization is constrained by variability in meal composition, interactions among components, fractionation efficiency, and scale-up requirements. This review examines how oil production routes affect meal composition and component accessibility, and summarizes physical fractionation, protein and polysaccharide recovery, and the separation, removal, or conversion of phenolic compounds, glucosinolates, and phytic acid. Applications of the resulting fractions in feed, fertilizer, foods, functional materials, bioactive products, and thermochemical conversion are evaluated. Existing evidence shows that pressing, solvent extraction, and thermal treatment alter residual oil content, protein solubility, protein-fiber associations, and the distribution of antinutritional compounds, thereby influencing subsequent separation. Fractionation conditions determine recovery, purity, structural state, and functionality and should be selected according to the intended product. Despite substantial progress, industrial implementation remains limited by feedstock variability, insufficient application-level validation, high water and chemical demand, and incomplete utilization of residual streams. Future work should define product-specific quality criteria, establish complete component mass balances, and develop continuous cascade fractionation processes with lower resource demand to support integrated and scalable rapeseed meal valorization.