Development of chitosan/dialdehyde starch active films incorporating apigenin-loaded zein/chia seed gum nanoparticles for strawberry preservation

In this study, an active packaging film with sustained release of active components was developed using nanoencapsulation. Apigenin (Ap)-loaded zein-chia seed gum nanoparticles (CSG/Zein@Ap NPs) were prepared via antisolvent precipitation. When CSG to zein mass ratio was 2:1, nanoparticles exhibited optimal encapsulation efficiency of 52.79%. Moreover, these nanoparticles exhibited favorable preliminary in vitro biocompatibility under the tested conditions. An active food packaging was prepared by CSG/Zein@Ap NPs into chitosan/dialdehyde starch film (CS/DSA). SEM and FTIR illustrated that the formation of Schiff base bonds and hydrogen bonds enhanced film’s compactness. Compared to chitosan film, when CSG/Zein@Ap NPs content reached 3 wt% (CS/DSA-3%NPs), tensile strength increased by 45.15%, while water vapor permeability decreased by 77.41%. The film exhibited excellent antibacterial and antioxidant properties (DPPH: 83.82%; ABTS: 94.19%), along with good biodegradability and soil microbial community regulation capabilities. Nanoencapsulation enabled Ap to exhibit sustained-release properties from film. Moreover, CS/DSA-3%NPs can extend the shelf life of strawberries by 6 days.