Study of the Physical, Chemical, and Structural Properties of Low- and High-Methoxyl Pectin-Based Film Matrices Including Sunflower Waxes

Abstract

The development of bio-based materials remains one of the most important alternativesto plastic materials. Although research in this field is growing, reporting various materials andmethodologies, it is still necessary to increase exploration. The aim of this work was to expand andcomplement previous research on the preparation and characterization of high- and low-methoxylpectin films obtained by casting, with the addition of commercial and recovered sunflower waxes.The results showed that the addition of sunflower waxes to the pectin matrix generated somediscontinuity in the aggregate, increasing the thickness and roughness of the film. However, due totheir hydrophobic nature, the waxes contributed to lower vapor transmission rate values of the films.On the other hand, the low-methoxyl pectin films had a more crystalline structure, which could helpto diminish water vapor permeability values, mechanical resistance and rigidity, and improve theirelongation. Regarding chemical characteristics, most of the raw materials? chemical groups werefound in the resulting films, and the presence of C-H bending due to pectin gelation was observed.Finally, the compatibility and contribution of pectin and sunflower waxes to the production of thefilms were demonstrated, as well as the possibility of using materials from industrial waste in foodpackaging applications.