Jiajie Zhou, Jiaxiu Du, Chaolin Zhou, Xinghua Zhou, Yirui Huang, Jiayun Huang, Hafiz Umer Javed, Yecheng Yang, Guanrong Wang, Yingying Wen, Zhengang Lin, Jingqi Shang, Mengmeng Zhang, Yingling Li, Cuijin Li, Xugang Shu, Li-Yan Zeng
Cherry tomatoes, valued as both fruit and vegetable (F&V), are prone to postharvest decay, leading to nutritional and economic losses. While chitosan-based preservation often involves complex designs, this study developed a simplified yet multifunctional edible alternative. A vitamin C deep eutectic agent (Vc-DEA) was synthesized and incorporated into chitosan (Ch) matrix as both plasticizer and antioxidant. The resulting Vc-DEA/Ch composite showed strong UV-blocking (300–380 nm) and concentration-dependent bioactivity, including notable antibacterial effects against Escherichia coli ( E. coli ) and the strongest antioxidant capacity in 80% variant (IC 50 values of 0.17 and 0.15 mg/mL for DPPH and ABTS, respectively). The 40% Vc-DEA saturated the chitosan matrix and co-formed a novel interpenetrating polymer network, yielding a morphologically uniform surface with modulated roughness (SEM), enhanced thermal stability (100–200 °C) (TGA), optimal mechanical property, and the most effective water vapor barrier. In a six-day ambient storage test on cherry tomatoes, the 40% Vc-DEA/Ch coating most effectively maintained firmness, modulated ripening through regulated lycopene synthesis, preserved nutritional quality (highest Vc content), and improved flavor, thereby enhancing marketability. This work establishes the 40% Vc-DEA/Ch composite as a sustainable and effective edible coating, offering a potential practical strategy to reduce postharvest decay in perishable produce. 40% Vc-DEA/Ch composite was developed as a sustainable and effective edible coating for cherry tomato preservation, offering a potential strategy to mitigate postharvest decay in perishable F&V. • Sustainable Vc-DEA/Ch composites for postharvest use. • 40% composite forms optimal network with enhanced barrier. • Strong UV-shielding, antioxidant, and synergistic anti-E. coli activity • 60/80% loadings cause phase separation and degrade key properties • 40% coating best delays senescence and maintains quality in cherry tomatoes