Multifunctional gelatin-based films for sustainable food packaging: Enhanced performance via silica nanoparticles

This study reports the fabrication of multifunctional gelatin-based films designed for sustainable food packaging, utilizing vanillin as a matrix enhancer and tannic acid as a natural crosslinking agent. Films were developed both with and without silica nanoparticles (NPs) to systematically evaluate their structural and functional properties. The resulting films exhibited high transparency alongside an effective UV-blocking capacity. While FE-SEM confirmed the complete physical self-healing ability of the films, mechanical testing quantified healing efficiencies at 52.30% for the silica-free films and an impressive 90.51% for those containing silica NPs. Chemical analysis revealed the synergy of Schiff base and hydrogen bonding interactions, with the latter identified as the dominant healing mechanism. Notably, the silica-containing film showed a reduced band gap energy of 2.66 eV, indicating enhanced photocatalytic potential. Furthermore, the fabricated films demonstrated robust barrier properties against water vapor and oxygen, as well as biodegradability, antioxidant activity, and antimicrobial effects against Staphylococcus aureus and Escherichia coli .