3D-printed biodegradable films for antimicrobial and antioxidant active packaging: application in grape preservation

Conventional food packaging contributes to environmental pollution and provides only passive protection. Here, biodegradable composite films were developed via extrusion-based 3D printing of alginate-gelatin-cellulose (AGC) hydrogels enriched with antimicrobial and antioxidant agents for active food packaging applications. Ink formulations were optimized to ensure printability, structural integrity, and functional performance. The films were systematically evaluated for antioxidant and antimicrobial activity, physicochemical and mechanical properties, and biodegradability. The optimized formulation containing essential oils increased radical scavenging from 4.17 ± 0.62% to 60.88 ± 0.71% and showed strong inhibition against Staphylococcus aureus and moderate activity against Escherichia coli and Pseudomonas aeruginosa. During storage, films reduced grape weight loss to 11-17%, versus 38-43% for polyethylene and 64-70% for unwrapped controls, while preserving color and firmness. These findings demonstrate potential of AGC-based bioactive films as sustainable packaging for extending the shelf life of perishable fruits.