Development, characterization and applications of chitosan-based biodegradable films enriched with essential oils for active food packaging

The present study was undertaken to develop and characterize chitosan-based biodegradable films incorporated with essential oils for active food packaging applications. Chitosan films were prepared using 1.0 and 1.5 per cent chitosan solutions incorporated with different concentrations (0.1, 0.2 and 0.3%) of lemongrass, tea tree, thyme and basil essential oils. The prepared films were evaluated for physicochemical properties, barrier properties, oxygen transmission rate and biodegradability. Film thickness ranged from 0.92 to 0.98 mm and increased slightly with increasing essential oil concentration. Incorporation of essential oils reduced swelling index, film solubility and water vapour permeability while improving water resistance due to enhanced hydrophobic interactions within the film matrix. Among the treatments, films incorporated with lemongrass oil showed superior water resistance, whereas, tea tree oil-incorporated films exhibited the lowest oxygen transmission rate among the EO-based films. Water vapour permeability was lowest in films containing 0.3 per cent tea tree oil and lemongrass oil. All films showed noticeable biodegradation within 30 days under soil burial conditions, confirming their eco-friendly and biodegradable nature. The results demonstrated that incorporation of essential oils improved the functional and barrier properties of chitosan films and enhanced their suitability as active packaging materials for food preservation and shelf life extension.