Chitosan‐Based pH‐Responsive Films and Edible Coatings to Enhance Fruit Shelf‐Life: Impact of Plant Biomolecules and Composition

Fresh fruits are a natural source of various minerals and vitamins, which are essential for human health. However, a rapid rate of respiration, water loss and fast ripening ability result in shorter shelf life and deterioration of perishable fruits. Biopolymeric material‐based edible coatings and packaging films can effectively enhance the shelf life of perishable fruits. In recent years, chitosan has been widely used as an effective material for the fabrication of edible coatings/films because of its excellent properties, such as edibility, biocompatibility, higher biodegradability rate and film‐forming properties. In addition, plant extract‐mediated phytochemicals are a significant natural source of antimicrobial agents. Thus, films based on combining plant phytochemicals and chitosan offer many benefits: reduced respiration rate, water loss, weight loss, inhibitory action against microorganisms and fruit freshness. Chitosan is a non‐toxic, eco‐friendly biopolymer with excellent film‐forming ability. This review study focuses on the basic approaches to prepare chitosan‐based edible coatings and films incorporated with plant extract and summarises the key role of components. The study also systematically examines the impact of plant biomolecules and giving particular attention is to recent strategies in the development of antimicrobial chitosan coatings and films to enhance postharvest fruit shelf life, along with pH‐responsive stimulus ability.