Maize starch-PVA nanocomposite biodegradable antimicrobial packaging films for enhancement of shelf-life of Agaricus bisporus

Abstract

Nanocomposite antimicrobial packaging can effectively cater to the postharvest losses of button mushrooms. This study aimed for fabrication of novel antimicrobial biodegradable packaging films using a double composite system comprised of nano-clay-essential oil (EO) composite blended with maize starch (MS) /Polyvinyl alcohol (PVA) polymers which was plasticized with glycerol. The results confirmed superior water barrier properties with the lowest film solubility (16.52 %) and water holding capacity (13.55 %) in MS+ PVA+ Nano-bentonite-basil EO blend film. The surface morphology of this blend film appeared smooth, was thermally stable with the lowest mass loss (97.92 %), and exhibited the highest tensile strength (182.15 Kg/cm2) which makes it suitable for food packaging applications. Furthermore, all the prepared films were fully degraded in the soil after 147 days except the control cling film. The addition of EOs enhanced the antimicrobial activity of starch blend films with the highest inhibition against Gram-positive microorganisms (Staphylococcus aureus and Listeria monocytogenes). Packaging of freshly harvested button mushrooms with nanocomposite blend film enhanced the shelf-life up-to 14 days of storage under refrigerated conditions (4 °C) with the lowest physiological weight loss (4.69 %) and highest firmness (1.5 Kg F). Nutritional qualities and ROS-mitigating enzymatic activity of mushroom fruiting bodies were also maintained through packaging. This innovative nanocomposite packaging films could provide a green, environment-friendly, and antimicrobial system to combat the shorter shelf life of button mushrooms.