Development of sodium caseinate/guar gum sheet biodegradable films with <i>Alhagi graecorum</i> extract for burger preservation

Abstract

Abstract This study aimed to develop environmentally friendly packaging films using a statistical optimisation approach—response surface methodology—to identify the most effective combination of sodium caseinate (SC), guar gum (GG), and Alhagi graecorum extract (AE) that would enhance mechanical properties. Key evaluations included surface morphology, mechanical performance, and thermal stability. The optimal film composition was achieved with 1.40 g of SC, 1.80 g of GG, and 1.66 g of AE dissolved in 250 ml of distilled water. The resulting films displayed notably improved homogeneity, mechanical integrity, and thermal resistance. They also demonstrated a significant reduction in water vapour permeability (1.01 × 10−10 g·m−1·s−1·Pa−1) and an increased water contact angle of 82.7°. Fourier-transform infrared spectroscopy analysis confirmed physical interactions between AE and the SC/GG matrix. Moreover, the incorporation of AE contributed to preserving beef burger quality throughout storage, highlighting the films’ potential for active packaging applications.