Molecular recognition-driven detection of β-Lactoglobulin: Mechanisms, progress and future prospects

β-Lactoglobulin (BLG), the principal allergen in bovine milk, exhibits strong immunogenicity and structural stability, posing notable challenges to food safety. Accurate detection of BLG is critical for allergen labeling and consumer protection. This review systematically summarizes molecular recognition strategies for BLG detection. It defines eight recognition modes and three binding sites, and categorizes seven recognition elements, including antibodies, aptamers, specific binding peptides, molecularly imprinted polymers, fluorogenic probes, metal nanozymes, and primers, based on binding mechanisms. Additionally, direct strategies utilizing BLG's intrinsic signatures, such as mass spectrometry and spectroscopy, are reviewed. Detection platforms are evaluated in terms of sensitivity, specificity, and applicability. Future perspectives highlight advances in intelligent sensing technologies, including integration with nanomaterials, microfluidics, and digital analysis. Emphasis is placed on achieving high performance under complex food conditions. This review provides a concise reference for developing next-generation BLG biosensors with improved accuracy, portability, and suitability for real-world allergen monitoring.