Using of Lignocellulosic Fiber Extracted from Artichoke Outer Petal Leaves as Filler in Potato Starch-Based Composite Films

Purpose Artichoke is an important vegetable of Mediterranean cuisine, however only 15–40% of globe artichoke weight consists of the edible parts. The rest of the plant which is discarded as waste is composed of many valuable components for further utilization. In this study, the alkali extracts of outer petal (bract) of globe artichoke (APE) which was discarded as processing waste was used as a lignocellulosic fiber source at different concentration in potato starch-based biodegradable composite food packaging films. Methods The effects of APE incorporation (0–20%, w/w based on starch) into starch-based composite films were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy, water vapor permeability (WVP), mechanical, thermal and optical properties. Results The WVP of the films were not significantly improved with the addition of APE, while FTIR spectra exhibited a possible interaction between starch and APE, since the peak intensity of the films changed with respect to the addition of APE into starch-based films. The tensile strength of the 10% APE film was the highest; however, 20% APE addition negatively affected the film strength. In contrast, the highest elongation at break value observed for 20% APE films ( P < 0.05). Although there was a clear tendency between the increment of the lightness, greenness and yellowness values upon the increased level of APE addition, the opacity of the films was found in the same group ( P > 0.05). Conclusions These results claimed that the addition of APE into S films could be a promising technique to improve the properties of biopolymers. Graphical Abstract