Potato peel valorization for nutraceuticals functional foods and sustainable bioproducts

This review critically evaluates potato peel, a major by-product of potato processing, as a sustainable source of nutraceutical and functional bioactives. The purpose is to synthesize current evidence on its nutritional composition, phytochemistry, bioaccessibility, safety, therapeutic potential, and industrial valorization, with emphasis on how recent processing and delivery strategies can convert this waste stream into higher-value products. Potato peel is rich in dietary fiber, phenolic acids, flavonoids, glycoalkaloids, resistant starch, proteins, enzymes, and minerals. These constituents may contribute to antioxidant, antimicrobial, anti-inflammatory, wound-healing, cardiometabolic, and food-stabilizing effects, although most evidence remains based on in vitro assays, animal models, and food-system studies rather than human trials. The review also highlights key limitations, including cultivar-dependent composition, glycoalkaloid safety thresholds, pesticide residues, variable bioavailability, limited clinical evidence, and scale-up challenges. Recent advances in green extraction, encapsulation, starch and protein recovery, biodegradable packaging, and nanoparticle synthesis show that potato peel valorization can support circular bioeconomy goals when supported by standardized processing, quality control, and safety assessment. Overall, potato peel should be considered a promising bioresource rather than a simple agro-food waste, but its health-related uses require careful formulation, dosage control, and stronger translational evidence.