From Rosehip Processing Waste to Functional Food Ingredients: A Critical Review of Rosa canina Valorisation Pathways

Rosa canina processing generates substantial residual biomass, including pomace, seed cake, and peel-associated fractions, underexploited despite high contents of vitamin C, fibre, phenolics, carotenoids, and seed lipids. This review critically synthesizes evidence on rosehip processing-residue composition, compares conventional and emerging extraction technologies, and evaluates validated food application pathways for waste-derived ingredients. Literature screening was combined with bibliometric term co-occurrence analysis to map the field and organize evidence into composition, extraction, application, and translation themes. The data show that rosehip pomace is a fibre- and polyphenol-rich stream suitable for drying, milling, and cereal-based foods, while seed-derived residues better support lipid recovery and secondary phenolic extraction. Ultrasound and microwave assisted extraction offer the best laboratory-scale phenolic recovery from solid residues, whereas supercritical CO2 extraction remains the most mature option for seed-oil recovery. Application studies indicate that rosehip-derived ingredients can improve antioxidant capacity, nutritional value, and functional positioning in bakery products, fermented dairy systems, meat formulations, and beverages, although texture changes, colour shifts, sedimentation, and flavour balance remain important constraints. Overall, the evidence supports rosehip waste valorisation as a technically feasible circular-economy strategy, but industrial implementation requires standardized raw-material characterization, route-specific mass balances, shelf-life validation, and techno-economic optimization.