Gelatin/ pectin based composite films re-enforced with mango peel extract loaded zein nanoparticles and zinc oxide nanoparticles: Enhanced mechanical and functional properties

Abstract

Gelatin (G), pectin (P), or their composite (G/P) films incorporated with mango peel extract (MPE) loaded zein nanoparticles (MZe), and zinc oxide nanoparticles (ZnO) were fabricated and characterized. MZe nanoparticles loaded with 8 mg/mL of MPE showed higher encapsulation efficiency (96.0 %), higher zeta potential (38.1), and lower PDI (0.13) compared to the lowered concentration of MPE. When films were fabricated using various combinations of polymers and nanofillers, scanning electron microscopy (SEM) revealed that the G/P composite with MZe-ZnO had compact and continuous structural integrity compared to other combinations. In addition, the G/P-MZe-ZnO composite film showed higher tensile strength (28 MPa) and elongation at break (28.4 %) compared to other formulations. Furthermore, incorporation of MZe and ZnO NPs in G/P composite film significantly enhanced hygroscopicity (>90 °C), light barrier properties (48.5 % transmittance), antioxidant (90.5 % DPPH radical scavenging activity), and antibacterial (Bacillus subtilis inhibition) activities. The results suggested that MZe and ZnO could be used as nanofillers to enhance the mechanical and active properties of the G/P composite film. The developed combination of composite film incorporated with nanofiller can be used as an active food packaging application.