Development and characterization of zein/gum Arabic nanocomposites incorporated edible films for improving strawberry preservation

Fresh produce waste, particularly strawberries, poses significant economic and environmental challenges across the entire supply chain. Bio-sourced polymers offer a sustainable alternative to systematic packaging materials, with edible active films gaining attention for their potential to improve food preservation and quality. This study focuses on the development and characterization of active edible films using zein and gum Arabic (GA), incorporating trans-cinnamaldehyde (TC) as an active compound. The films were systematically evaluated for their physical, microscopic, mechanical, barrier, antioxidant, and antibacterial properties. Film-forming emulsions formulated with varying zein to GA ratios showed stable particulate sizes ranging from approximately 260 to 450 nm with uniform distribution and Newtonian fluid behavior, crucial for practical application. Compared to zein-only films, these films showed smoother surfaces, reduced roughness, and enhanced mechanical properties with tensile strength up to 2.63 MPa and elongation at break reaching 85.99%. Barrier assessments demonstrated tunable moisture, gas permeability, and UV protection. The films exhibited potent antioxidant and antibacterial activities against Escherichia coli and Listeria innocua, with an inhibition rate exceeding 99%. Application of these films on strawberries demonstrated multifunction including prolonged shelf-life, maintaining appearance, reducing weight loss, preserving firmness, and controlling microbial populations under both ambient and refrigerated conditions. Overall, these findings underscore their potential as innovative, sustainable packaging materials for extending the shelf-life of fresh produce.

Graphic abstract