Preparation and characterization of gelatin/Kappa-carrageenan halochromic films containing curcumin for active and smart food packaging

Gelatin (GE) and Kappa carrageenan (KC) are prominent examples of natural, biodegradable polymers for food packaging. In this study, edible films were fabricated using various GE:KC ratios (25:75, 50:50, 75:25), and distinct concentrations of curcumin (Cur; 1%, 2%, and 4%). Then, spectroscopic assessments were conducted, including Fourier transform infrared (FTIR), morphological characterization via scanning electron microscopy (SEM), and sensitivity to pH variations. Furthermore, the efficacy of these halochromic films in preserving food quality and inhibiting spoilage was assessed. It was shown that the incorporation of Cur to GE-KC hybrid films produces an active and smart biodegradable film with a suitable color identifier. Adding Cur to GE-KC polymer significantly decreased the solubility and permeability of the optimal films compared to the control samples (without Cur) (p