|
چکیده
|
Bionanocomposites starch films containing ZnO nanoparticles were prepared by casting method from corn starch solutions. The nanoparticles of ZnO were homogenized by sonication and incorporated into corn starch solutions at different concentrations (e.g. 1%, 3%, 5%, and 7% w/w dried starch). Fresh strawberries were then packed in the polypropylene packages covered with these bionanocomposites, to be used as cap of packaging, and stored at 4oC. Microbial stability of the fresh strawberry was evaluated after 4, 8, 12, 16 and 20 days of storage. Dispersion quality of antimicrobial nanoparticle within the polymer matrix films were assessed by Transmission Electron Microscopy analysis (TEM) and the mechanical properties of them were characterized by using Young's Modulus analysis. The results showed that microbial growth rate significantly reduced as a result of using this nanocomposite packaging material by up to 20 days. The TEM results revealed that ZnO nanoparticles with spherical and granular morphology had uniform distribution within starch polymer. Moreover, Young’s Modulus for all of the nanocomposites increased with the increasing filler loading. Consequently, ZnO nanoparticles have the potential as a filler in starch-based films for use as an antimicrobial packaging materials which help to extend the shelf life of fresh strawberry to 20 days.
|