Molecular interactions and functional performance of jicama starch–CMC films and coatings in extending banana shelf life

Abstract

Jicama starch (JS), an underutilized starch source, was examined in combination with carboxymethyl cellulose (CMC) for the purpose of developing edible films and coatings. We analyzed films based on JS (3 % w/v) that contained CMC (0.5–1.5 % w/v) for their structural, thermal, mechanical, and barrier properties. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) confirmed the presence of intermolecular interactions, whereas thermogravimetric analysis (TGA) demonstrated increased stability at elevated CMC levels. Scanning electron microscopy (SEM) confirmed that the incorporation of JS with CMC resulted in the transformation of the fragile and cracked JS matrix into a compact and homogeneous structure. Enhanced CMC levels resulted in improved tensile strength while simultaneously reducing transparency, solubility, and water vapor permeability, thus enhancing its suitability for packaging applications. Contact angle measurements for functional evaluation indicated enhanced wettability and diffusivity of JS–CMC coatings on banana peel surfaces. JS–CMC coatings applied to ethephon-treated bananas stored at 25 °C effectively reduced weight loss, malondialdehyde accumulation, and electrolyte leakage, while also delaying peel discoloration and changes in soluble solids and titratable acidity associated with ethephon-induced ripening. The results indicate that JS–CMC blended films/coatings exhibit adjustable hydrocolloid properties with practical functionality in delaying chemically induced ripening, highlighting their potential as sustainable, plant-based materials for edible packaging.