Biodegradable and gelatin-based composite films incorporating Lactoferrin-Nisin active nanoparticles: Preparation, characterization, antibacterial applications of cheese and chicken

• The incorporation of l -N nanoparticles enhanced the properties of gelatin films. • G/L-N films show oxygen and UV barrier properties and antioxidant activity. • G/L-N films are biodegradable and represent an environmentally friendly material. • G/L-N films could be applied in food packaging, particularly for chicken and cheese. Food packaging plays a critical role in maintaining the quality and safety of food. The development of biodegradable films that are effective in food preservation and environmentally friendly is essential. The aim of this study was to develop an active gelatin-based composite film with enhanced functional properties by incorporating Lactoferrin-Nisin nanoparticles (L-N NPs) for food preservation applications. In this study, L-N NPs were successfully prepared using a self-assembly method, and different concentrations of L-N NPs (0.1 %, 0.2 %, and 0.4 % w/v) were incorporated into gelatin-based films to produce active composite films (G/L-N) with antioxidant and antibacterial properties. Statistical analysis (ANOVA, p <0.05 ) revealed that the incorporation of L-N NPs significantly improved the films’ mechanical and functional properties compared to pure gelatin films. The elongation at break (EAB) of G/L-N 0.4 % increased to 131.94 ± 7.38 % (vs. 70.04 ± 6.93 % for pure gelatin films), while light transmittance at 280 nm is 9.60 ± 5.58 (control:38.44 ± 9.63 %). Antioxidant activity was significantly enhanced, with DPPH radical scavenging rates of 22.30 ± 2.33 % (control: 8.01± 1.16 %) and ABTS scavenging rates of 45.72 ± 4.67 % (control: 6.81± 2.48 %) ( p <0.05). Furthermore, these films effectively prevented the penetration of bacteria into the surfaces of cheese and chicken, while inhibiting the growth of Listeria monocytogenes and Staphylococcus aureus in both foods. Cold storage studies indicated that G/L-N films helped slow pH changes, reduce moisture loss, preserve color, and maintain the texture and sensory properties of cheese and chicken. In addition to the above functions, G/L-N films have the advantages of green environmental protection, simple synthesis, and so on. These findings highlight the potential of G/L-N films for effective food preservation and shelf-life extension, suggesting their potential use as biodegradable active packaging materials for food preservation.