Exudate-responsive chlorine dioxide system reshapes microbial ecological dynamics for smart preservation of chilled...

Chilled meat, typically distributed and stored in tray packaging, is prone to accelerated spoilage due to the accumulation of exudate at the bottom of trays. To address this challenge, the study developed an exudate-responsive system using 3D printing. This system comprises a 3D-printed substrate and chlorine dioxide tablets (ClO₂-CTs). The former acts as a physical barrier to separate the meat from accumulated exudate, while the latter enables on-demand ClO₂ release upon contact with the exudate. This study further investigated the preservation efficacy of the developed system on chilled mutton. The responsiveness of the system was simulated based on the exudate production patterns of chilled mutton observed in preliminary experiments. A minimal volume of water (10 μL) was sufficient to trigger the release of 0.11 mg/m³ of ClO₂, validating the rapid responsiveness of the developed system. The maximum release rate of each tablet is 0.95 mg/m³. Antibacterial results indicate that this system (5 ClO₂-CTs, 4.85 mg/m³) achieved significant inhibition against 6 indicator bacteria. Further mechanistic studies confirmed that ClO₂ was responsible for this antibacterial effect, via the induction of oxidative stress and disruption of microbial cell membrane integrity. Preservation trials demonstrated that the system effectively maintains the quality of chilled mutton. Furthermore, the system significantly reduces the abundance of Acinetobacter and Psychrobacter, achieving excellent preservation effects by reshaping the microbial ecosystem during storage. This study illuminates the significant potential of the exudate-responsive system as a novel preservation technology for chilled meat.