Synthesis and applications of chitosan derivatives in food preservation-A review

Food spoilage is a global problem nowadays that requires food preservation during storage. Food spoils every year and becomes inedible causing a shortage of food. We are focused on biopolymers especially chitosan having antioxidant and antibacterial properties for the production and application of chitosan (CS) derivatives-based coatings and films for food preservation. Chitosan derivatives are synthesized through processes like derivatization and integration with advanced technologies, enhancing their functional properties. These derivatives exhibit antimicrobial, antioxidant, and biodegradable characteristics, making them ideal for food preservation. They help extend the shelf life of various food products by inhibiting microbial growth and oxidation. Additionally, chitosan-based films and coatings are used as natural preservatives, reducing the need for synthetic additives. Ongoing research aims to overcome current challenges and optimize their applications in the food industry. First, we summarized the modification methods for chitosan derivatives formation e.g., alkylation, acetylation, quaternization, phosphorylation, sulfonation, graft copolymerization, and Schiff's base reaction. Then we discussed research progress on chitosan derivatives-based films and coatings for a variety of foods such as vegetables, fruits, juice, meat, dairy products, and functional foods. In this review paper, we collected literature from very recent years (2020–2023) to evaluate the advancements in chitosan derivative synthesis and their application as nanocomposites, nanoparticles, thin films, etc. in food preservation. The review article explores the innovative synthesis techniques and diverse applications of chitosan derivatives in enhancing food preservation.