A thorough evaluation of chitosan-based packaging film and coating for food product shelf-life extension

Chitosan is a cationic polysaccharide and derived from chitin present in exoskeleton of crustaceans such as prawns, crabs, and lobsters. This natural biopolymer chemical structure is identical to cellulose but insoluble in aqueous and organic solvents. Chitosan is an ecologically beneficial biodegradable alternative to synthetic polymers, notably typical plastics. Chitosan may be used to make a variety of films, coatings, and membranes, each having its own distinct features. Chitosan films are biodegradable, translucent, and have high mechanical strength, making them adequate for food packaging, water purification, and wound dressings. Chitosan-based films and coatings are often used for packaging foods such as fruits and vegetables, meat, and seafood. According to the findings, chitosan films have outstanding barrier qualities against UV radiation, gases, and moisture. They can assist in safeguarding packed objects from outside influences such as oxidation and humidity, which could degrade their quality. Chitosan's antibacterial qualities naturally limit the development of bacteria, viruses, and fungi. Because of this property, chitosan-based films are useful for packaging perishable food products since they may extend shelf life by lowering microbial contamination. Modifying the chitosan content or adding additional components can change the mechanical strength and flexibility of the film. Surfaces may be treated with chitosan coatings to improve qualities such as water resistance, barrier properties, and antibacterial activity. This review article discusses different approaches such as solvent casting, extrusion, electrospinning, thermoplastic method, layer-by-layer assembly, spraying, dipping for the preparation of chitosan-based films and coatings. Further these food packaging material properties such as viscosity, thermal properties, optical properties, solubility, hydrophobicity, color, mechanical characteristics, barrier qualities, antibacterial properties, antioxidant activity and prolonging the shelf life of products is described in depth.