Advances in oil-based edible coatings for postharvest preservation of fruits and vegetables: A comprehensive review of biopolymer types, functional plant oils, nanoemulsion systems, and application techniques

The rapid deterioration of fruits and vegetables after harvest remains a significant challenge in ensuring food quality, safety, and sustainability. Oil-based edible coatings provide an eco-friendly solution to prolong shelf life, minimize postharvest losses, and reduce reliance on synthetic packaging. This review focuses on the distinctive role of oil-based matrices in edible coatings, emphasizing their essential function as hydrophobic barriers that effectively reduce moisture loss and gas exchange, thereby preserving produce freshness. The integration of functional plant oils into polymer-based coatings imparts additional benefits, such as antimicrobial properties, antioxidation, and enhanced mechanical stability. Nanoemulsion technologies further augment the stability and bioavailability of these active compounds, enabling more effective preservation without compromising the quality of the coated produce. The review also explores the types of polymers—natural, synthetic, and biodegradable—that form the structural foundation of these coatings and the various application techniques, such as immersion, spraying, and advanced methods, that influence coating performance. By examining the chemical composition, application techniques, and functional attributes of oil-based coatings, this study provides insight into their potential for sustainable postharvest management in the food supply chain.