Multifunctional sodium alginate/nanocellulose fibers/chitosan edible coating: A sustainable strategy for prolonged fruit preservation and reduced cold-chain dependency

Fruits and vegetables are highly susceptible to storage conditions; therefore, the long-term preservation of fresh produce without cold-chain storage remains a remarkable challenge to food security. Herein, we synthesis a multifunctional, edible coating based on sodium alginate (SA) reinforced with nanocellulose fibers (NCFs) and chitosan (CS). The results showed that the monomers were crosslinked by hydrogen, ester bonds, and electrostatic interactions in the composite coating. Meanwhile, SA/NCFs/CS exhibited excellent mechanical properties (elongation: 101 %; tensile strength: 88.92 MPa; toughness: 6.59 MJ/m 3 ). Additionally, the composite coating displayed excellent antioxidant (96.33 %), antibacterial (99.02 %) and biocompatibility (99.99 %). The preservation experiment showed that, at 4 °C, the composite coating could extend the shelf life of bananas and strawberries to 12 days. It thus facilitates the long-term preservation of various fruit types and reduces the costs associated with cold-chain transportation. Thus, this study offers a novel perspective for developing multifunctional, edible preservation materials, providing a sustainable and effective alternative to traditional cold-chain-dependent storage methods.