A comparative study: Physical, mechanical and antibacterial properties of bio-composite gelatin films as influenced by chitosan and zinc oxide nanoparticles incorporation

Abstract

This study focuses on a comparison of bio-nanocomposites films with the addition of chitosan nanoparticles (organic) and zinc oxide nanoparticles (inorganic) in order to evaluate their affinity with bovine gelatin. The addition of organic and inorganic nanoparticles into gelatin/tapioca starch films were evaluated on its thickness, thermal, structure, barrier, mechanical and antibacterial properties. The addition of nanoparticles increased the film thickness. However, inorganic nanoparticle films showed more thermal stable compared to organic nanoparticle films. Moreover, the formation of Amide A, Amide I, and Amide II bands in the films structure, affecting the barrier properties of the film (p < 0.05). The incorporation of inorganic nanoparticles increased tensile strength (0.20–0.22 MPa) and decreased the elongation at breaks (131.80–94.55%) as well as film solubility. Furthermore, the gelatin-based bio-nanocomposite films showed antibacterial properties against Staphylococcus aureus and Escherichia coli. The inorganic nanoparticles had larger inhibition zone as compared to the organic nanoparticles. These findings indicate that inorganic nanoparticles have the potential to be incorporated with gelatin films to produce bio-nanocomposite films with better characteristics as food packaging.