Prospects and challenges of using optical probes to detect cadaverine in assessing the freshness of animal-based foods

Cadaverine, an aliphatic biogenic amine formed by the decarboxylation of lysine, serves as a marker of food spoilage. Therefore, developing rapid and specific real-time detection methods and tools for cadaverine is crucial for assessing food freshness. Compared to traditional methods, colorimetric and fluorescent approaches enable simple, non-destructive, rapid on-site detection with nanomolar detection limits, supporting real-time food monitoring in supply chain scenarios. This paper reviews the current status of colorimetric and fluorescent putrescine detection technologies based on reaction types. It further explores the integration of colorimetric and fluorescent methods with smart food label films as a future trend in food freshness detection, though significant challenges remain in technology, market requirements, and standardization. The development of colorimetric and fluorescent cadaverine detection technologies reviewed herein, particularly the more precise fluorescent detection methods, will provide critical theoretical foundations and technical support for real-time monitoring of food freshness.