Advances in gum Arabic utilization for sustainable applications as food packaging: Reinforcement strategies and applications in food preservation

The petrochemical plastic-based materials have been widely applied for food packaging. However, petrochemical plastic waste will result in large amounts of non-degradable pollutants that cause environmental challenges and health concerns. Therefore, the study on environment-friendly and biodegradable food packaging has garnered much attention. Gum Arabic (GA) presents great film-forming capacity, biocompatibility, and biodegradability, which support its applications for food packaging. The review addresses the main modification strategies for GA-based films to obtain improved physical properties (i.e., mechanical, barrier, and thermal properties) and functional properties (e.g., antioxidant, antimicrobial, and pH-responsive properties). Furthermore, the potential applications of GA-based films into food preservation were comprehensively reviewed. Some strategies, including introducing nanomaterials, natural plant extracts, essential oils, and plant oils and blending with other biopolymers, were reported to be effective in improving the physical properties of GA-based films, represented by the strengthened mechanical, barrier, and thermal properties. Additionally, the introduction of bioactive ingredients was found to impart excellent antioxidant and antimicrobial properties on GA-based films. Besides, some natural pigments (e.g., anthocyanins) could be incorporated as colorimetric indicators to fabricate smart GA-based films that provide real-time information on food freshness. Importantly, GA-based films could be utilized for the preservation of various foods, predominantly including fruits, vegetables, meat, livestock, and aquatic products, edible oils, and nuts, and the functionalized GA-based films with antioxidant and antimicrobial capacities presented improved preservation effects.