Structure-property correlations and environmental impact assessment of sustainable antibacterial food packaging films reinforced with fungal chitin nanofibrils

This study develops sustainable, antibacterial food packaging films using carboxymethylcellulose and fungi-derived chitin nanofibrils (ChNFs) reinforced with clay to enhance mechanical strength, moisture resistance, and gas barrier properties. ChNFs significantly improve tensile strength and permeability by forming a dense, hydrogen-bonded network within the carboxymethylcellulose matrix. However, excessive ChNF content led to agglomeration, reducing mechanical performance slightly. At 30% ChNFs content, films demonstrated antibacterial activity against Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes and also presented a 52.1 ± 3.2% degradation rate in four weeks. Life cycle assessment revealed a reduced carbon footprint (5.0–5.3 kg CO₂-equiv. per kg film) and low plastic litter generation (35–44 g/kg), underscoring environmental benefits compared to conventional packaging. These carboxymethylcellulose/ChNF-based films are a promising, eco-friendly alternative for food packaging applications, offering antibacterial properties and enhanced sustainability in the packaging of perishable food products.