Development and application of hydrogels in pathogenic bacteria detection in foods

Hydrogels are 3D networks of water-swollen hydrophilic polymers. It possesses unique properties (e.g., carrying biorecognition elements and creating a micro-environment) that make it highly suitable for bacteria detection (e.g., expedited and effective bacteria detection) and mitigation of bacterial contamination in specific environments (e.g., food systems). This study first introduces the materials used to create hydrogels for bacteria detection and the mechanisms for detection. We also summarize different hydrogel-based detection methods that rely on external stimuli and biorecognition elements, such as enzymes, temperature, pH, antibodies, and oligonucleotides. Subsequently, a range of widely utilized bacterial detection technologies were discussed where recently hydrogels are being used. These modifications allow for precise, real-time diagnostics across varied food matrices, responding effectively to industry needs for sensitivity, scalability, and portability. After highlighting the utilization of hydrogels and their role in these detection techniques, we outline limitations and advancements in the methods for the detection of foodborne pathogenic bacteria, especially the potential application of hydrogels in the food industry.