Production of Na-Alginate based biodegradable active films using bio-waste for cherry tomato packaging applications

Abstract The development of sustainable food packaging is one of the most promising approaches to reducing the negative impact of petroleum-based plastics on the environment and health. This study aimed to develop alginate-based active films incorporating banana, pomegranate, and citrus peels, to characterize their properties, and to assess their potential for food packaging applications. For the first time, these fruit peels were systematically compared within the same study, providing unique insights into their relative performance in film formation. In addition, citric acid (CA), a non-toxic cross-linker, was used instead of conventional salts, increasing both safety and sustainability. To benefit from their inherent antioxidant properties, the peels were incorporated directly into the film formulations. Sodium alginate (Na-Alg), a biocompatible polymer, served as the film matrix. The four synthesized films were evaluated in terms of crystallinity, thermal stability, chemical composition, physical properties, and applicability in tomato packaging. Notably, the addition of fruit peels not only enhanced the antioxidant activity of the films but also reduced their water vapor transmission rate (WVTR), effectively minimizing weight loss in the coated tomatoes. Overall, this work demonstrates the potential of incorporating fruit peels to transform food waste into value-added, eco-friendly packaging materials, thereby extending food shelf life and reducing environmental impact.