Characterization of physical, mechanical, and antibacterial properties of agar-cellulose bionanocomposite films incorporated with savory essential oil

In this study, different concentrations of savory essential oil (0.5, 1, and 1.5%) were incorporated into agar-based nanocomposite films as active packaging in order to evaluate their physical, mechanical, and antimicrobial properties. X-ray diffractometry (XRD) and scanning electron microscopy (SEM) were performed to explain the structural properties and morphology of these films. Incorporation of savory essential oil (SEO) into nanocomposite films decreased tensile strength and Young's modulus, but increased the percent elongation at break. In addition, water solubility decreased when SEO was incorporated into the films, whereas it did not significantly affect water vapor permeability. The films containing SEO were more effective against gram-positive bacteria (Listeria monocytogenes, Staphylococcus aureus and Bacillus cereus) than gram-negative bacteria (Escherichia coli). Results suggested that the agar-based nanocomposite films containing SEO can be used as active packaging for improving the safety and shelf-life of foodstuff. (C) 2014 Elsevier Ltd. All rights reserved.