Biobased films from unconventionally sourced starch (Cucurbita foetidissima Kunth) and oregano essential oil (Lippia berlandieri Schauer): A look at their physicochemical properties

Abstract

Buffalo gourd root starch (BGRS) and Mexican oregano essential oil (OEO) were used to obtain bioplastic films. The effect of different concentrations of OEO (0, 0.1, 0.3, 0.5, and 1.0% w/w in relation with starch) on the films physicochemical properties was evaluated. The additive inclusion significatively impacted on optical, mechanical, permeability, thermal, wettability, and morphological properties compared to the control, outstanding this effect on samples at low OEO concentrations (0.1 and 0.3% w/w respect to the BGRS), due to its component’s plasticizer capacity. FTIR analysis evidenced the different degrees of material’s components mixtures integration through the possible formation of hydrogen bonds to which the changes in the physicochemical properties of the obtained films could be attributed. SEM micrography showed an appropriated components integration for 0.1 and 0.5% OEO concentrations. According to their properties, these films may have a greater possibility to have practical applications, including food packaging.