Effects of virgin coconut oil on the physicochemical, morphological and antibacterial properties of potato starch-based biodegradable films

摘要

This study investigated the effects of adding different concentrations of virgin coconut oil (VCO) on the optical, mechanical, thermodynamic and antimicrobial properties, as well as water vapour permeability and morphology of potato starch-based biodegradable films. Increasing VCO concentrations caused a rise in the light transmittance of the films from 2.13 to 4.79 mm(-1) and a decrease in water vapour transmittance from 6.77 to 2.12 (10(-5) GPa(-1 )h(-1 )m(-1)). At a VCO concentration of 14 wt% (based on potato starch), the tensile strength reached its highest value (19.98 MPa). Scanning electron microscopy showed that the surface of the film became smoother as VCO concentration increased. The addition of VCO inhibited the growth of Listeria monocytogenes, Staphylococcus aureus and Escherichia coli. In conclusion, VCO supplementation improved the mechanical, antibacterial and water barrier properties of starch-based films. These results could expand the scope of the application of starch-based films in food packaging.