A colorimetric hydrogen sulfide (H2S) sensor based on gellan gum capped silver nanoparticles was developed to real-time monitor meat spoilage. The colorimetric sensor strategy was attributed to the ultrastrong binding ability of Ag with H2S to form Ag2S. The sensor enables the analysis of H2S with a limit of detection (LOD) of 0.81 μM, and it exhibited excellent selectivity toward H2S against other volatile components generated from chicken breast and silver carp during spoilage. By these virtues, the sensor presented visible color changes from yellow to colorless by in situ and nondestructively sensing H2S generated from chicken breast and silver carp in a packaging system. This strategy provided a simple but useful, non-destructive, robust, cost-effective, and user-friendly platform to real time monitor meat spoilage for intelligent food packaging.

The application of smart packaging technology in fruit and vegetable preservation has shown significant potential with the ongoing advancement of science and technology. Smart packaging leverages advanced sensors, smart materials, and Internet of Things (IoT) technologies to monitor and regulate the storage environment of fruits and vegetables in real time. This approach effectively extends shelf life, enhances food safety, and reduces food waste. The principle behind smart packaging involves real-time monitoring of environmental factors, such as temperature, humidity, and gas concentrations, with precise adjustments based on data analysis to ensure optimal storage conditions for fruits and vegetables. Smart packaging technologies encompass various functions, including antibacterial action, humidity regulation, and gas control. These functions enable the packaging to automatically adjust its internal environment according to the specific requirements of different fruits and vegetables, thereby slowing the growth of bacteria and mold, prolonging freshness, and retaining nutritional content. Despite its advantages, the widespread adoption of smart packaging technology faces several challenges, including high costs, limited material diversity and reliability, lack of standardization, and consumer acceptance. However, as technology matures, costs decrease, and degradable smart packaging materials are developed, smart packaging is expected to play a more prominent role in fruit and vegetable preservation. Future developments are likely to focus on material innovation, deeper integration of IoT and big data, and the promotion of environmentally sustainable packaging solutions, all of which will drive the fruit and vegetable preservation industry toward greater efficiency, intelligence, and sustainability.