Development and Characterization of a Novel Edible Film Based on Carboxymethylcellulose-Beta-Glucan Containing Inulin: Mechanical, Barrier and Structural Characteristics

Background and Objectives: Bioactive packaging systems (coatings/films) are novel technology concepts in food industries. Bioactive compounds such as antioxidants, vitamins, probiotics and prebiotics are designed to be included in coatings or coating materials that directly affect health of consumers. The aim of this study was to assess feasibility of producing prebiotic edible films by adding inulin to the film based on carboxymethyl cellulose and beta-glucan and to investigate film mechanical, barrier and structural characteristics.  Materials & Methods: In this study, various concentrations of inulin (0, 2 and 4% w/v) were added to carboxymethylcellulose/beta-glucan solutions. Then, mechanical (tensile strength and elongation at break), barrier (oxygen and water permeability), optical (opacity, a, b and L) and structural characteristics of the films were compared with each other. Results: Inulin included plasticizing effects in all treatments. Thus, tensile strength decreased and hydrophilicity, oxygen permeability and elongation at break increased significantly (p < 0.05). Fourier-transform infrared spectroscopy analysis showed that hydrogen bonds were the major force between carboxymethylcellulose, beta-glucan and inulin, which increased flexibility and water affinity of the films. Conclusion: Although addition of inulin improved composite films via increases in elongation at break and decreases in oxygen permeability of the composite films, their hydrophilicities increased as well. Therefore, these films include the potentials in cases, where packaging hydrophilicity is an advantage such as edible coating used in food products. However, further studies seem necessary.