Preparation and properties of edible active films of gelatin/carboxymethyl cellulose loaded with resveratrol

Abstract

Resveratrol (Res) powder was incorporated into gelatin (GEL)/carboxymethyl cellulose (CMC) film-forming solutions to create GEL/CMC-Res composite films (G/C-R) without the use of organic solvents. The study focused on how phase separation affected the properties of these films. The film formation mechanism of the G/C-R films was analyzed using infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The findings revealed that the Res powder was evenly distributed within the GEL/CMC film matrix, which enhanced the crystallinity and surface roughness of the films, contributing to improved surface hydrophobicity. Dynamic rheological analysis showed that the presence of Res increased both the modulus and viscosity of the film-forming solutions. Thermal analysis, including differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA), indicated that Res elevated the phase transition temperature, decreased the rate of thermal degradation, and enhanced the thermal stability of the films. Additionally, Res reduced water vapor permeability (WVP) by 75 % and significantly boosted antioxidant activity from 15 % to 85 %. This study demonstrates that the dispersion of Res powder in G/C-R blend films markedly improves their water barrier and antioxidant properties, effectively inhibiting the oxidation of soybean oil, and highlighting their potential as active packaging for food.