Preparation and characterization of a novel bionanocomposite edible film based on pectin and crystalline nanocellulose

In this study, for the first time, the edible pectin film was reinforced by crystalline nanocelullose (CNC). The incorporation of three levels of CNC (2, 5 and 7% w/w) on mechanical, thermal and water vapor barrier properties of pectin-based biodegradable film were investigated using solution casting evaporation method for film preparation. The optimum result was obtained through the nanocomposite film with 5% CNC in terms of mechanical and water vapor properties as the tensile strength increased up to 84% and water vapor permeability decreased by 40%. However, analysis of thermal properties indicated no significant effect of CNC on glass transition temperature. X-ray diffraction (XRD) studies illustrated a positive correlation between the degree of crystallinity and the CNC level. Moreover, AFM images presented good dispersion of CNC in the pectin matrix suggesting appropriate interaction between the filler and matrix, which is in agreement with mechanical consequences. According to the overall results, the reinforcement of pectin film with 5% CNC compared to other strengthening strategies had a higher effect and therefore it could be introduced as a good candidate for the development of strong, completely biodegradable and renewable food packaging material.