Influence of Maltodextrin on the Physicochemical Properties of Chitosan- and Starch-Based Biopolymeric Matrices for Active Packaging

In this study, the effect of incorporating maltodextrin into films composed of thermoplastic starch and chitosan was evaluated with the aim of improving their physicomechanical properties. X-ray diffraction revealed greater organization in sample TPS-CH-M3 compared with TPS-CH-M0 and TPS-CH-M5, indicating a balanced semicrystalline structure. Thermal analyses showed an increase in the glass transition temperature from 63.0 °C to 72.6 °C and a shift of the main degradation step from 308 °C to 311 °C, reflecting enhanced thermal stability. The contact angle decreased from 89.5° to 74.0°, confirming increased hydrophilicity. SEM micrographs revealed a homogeneous surface in TPS-CH-M0 and controlled roughness in TPS-CH-M3. Mechanical tests recorded the highest tensile strength (12.5 MPa) and elongation at break (18%) for TPS-CH-M3. FTIR spectra showed physical interactions without new chemical bands, and colorimetric analysis indicated an increase in yellow tonality, which is suitable for packaging and coatings of light-sensitive foods.