Active Films Based on Gelatin and Modified Curcumin: Physicochemical Properties and Food Packaging Application

This study investigated the development of active gelatin films containing modified curcumin and their application to reduce browning of banana peels. Curcumin, a natural antioxidant with limited water solubility, was modified through antisolvent precipitation, which obtained modified curcumin (MC) with increased water solubility and higher antioxidant activity. Gelatin films with different MC concentrations (0.0%, 0.1%, 0.3%, 0.5%, and 1%) were produced by the casting method. The resulting films were tested for thickness, morphology, crystallinity (XRD), chemical bonds (FTIR and Raman), water adsorption, water solubility, optical properties, wettability, water vapor permeation, mechanical properties, and antioxidant activity. Furthermore, the antioxidant film properties were evaluated using bananas as a food model. Structural analyses (XRD, FTIR, and Raman) confirmed that MC was well-incorporated without modifying the film's thickness, permeability, wettability, and mechanical properties. Scanning electron microscopy (SEM) showed a uniform distribution of MC, and the antioxidant activity (DPPH and ABTS assays) increased as a function of MC concentration. Gelatin films containing 1% MC reduced the browning of banana peels during the storage of this fruit at 25 degrees C and 75% RH for 6 days. These findings highlight the potential of gelatin films containing MC as a sustainable bioactive packaging with promising food applications.