Edible coatings as modulators of enzymatic pathways in postharvest fruit metabolism - A comprehensive review

Postharvest fruit deterioration is governed by tightly coordinated enzymatic networks that regulate cell wall disassembly, carbohydrate conversion, and redox balance. Although edible coatings are widely applied to reduce respiration and moisture loss, their role is increasingly recognized as extending beyond passive barrier formation. Emerging evidence indicates that coatings function as metabolic regulators capable of modulating enzyme activity, hormonal signalling, and oxidative homeostasis in both climacteric and non-climacteric fruits. However, a mechanistic synthesis linking coating-induced micro environmental modifications to specific enzymatic pathways remains limited. This review conceptualizes edible coatings as regulatory interfaces that influence three major enzymatic domains: cell wall-degrading enzymes, carbohydrate-metabolizing enzymes, and oxidative-antioxidant systems. Particular emphasis is placed on contrasting ethylene-driven enzymatic cascades in climacteric fruits with hormone- and stress-mediated regulation in non-climacteric systems. We integrate physiological, biochemical, and emerging multi-omics' evidence to propose a unified pathway model linking coating properties to enzymatic modulation and quality preservation. By positioning edible coatings as tools for precision metabolic regulation, this review provides a transformative framework for designing next-generation postharvest preservation systems.