Study of Nano Composite Films Made of Starch and Chitosan with Silver Nanoparticles and Comparison of their Antimicrobial Effects

Food packaging is a vital approach for ensuring food safety. Due to the high importance of food packaging, nanotechnology can improve packaging quality and consequently ensure the safety.
Nanosilver particles were synthesized and starch-based nanocomposite films, chitosan with the content of 0, 250 and 500 ppm nanosilver particles were produced and their properties including mechanical properties, water vapour permeability, solubility, swelling and anti-microbial properties of the produced films were studied by measuring the diameter of the bright area in the disk permeability test. In this test, four types of bacteria including Staphylococcus aureus, Escherichia coli, Aspergillus niger and Candida albicans were employed. The colour changes in the films after the addition of nanosilver were examined and the size of synthesized nanosilver particles was determined by using DLS.
The addition of nanosilver to the films increased the water vapour permeability. Tensile strength was increased and this increase in the case of chitosan films was significant whereas in the case of starch film was not significant. Elongation at break was also increased in all the films. Although the addition of nanosilver increased the solubility and swelling, this increase was not significant. Films containing nanosilver has an antimicrobial effect on all the microorganisms that were investigated (p In general, the properties of the films produced by nanosilver particles were completely affected by the concentration of the used nanosilver except for water vapour permeability where this led to improvement of the properties of the films.