Species- and heat-dependent variability in shrimp allergens revealed by quantitative proteomics: Implications for...

Shellfish allergy is a major cause of food-induced severe adverse reactions worldwide, with shrimp representing one of the most implicated triggers. Detection and monitoring of allergenic proteins in shrimp-containing foods rely largely on immunoassay-based detection, typically targeting tropomyosin without species-level specificity. However, allergen composition may vary across species and processing conditions, limiting the accuracy of existing approaches. Here, we applied quantitative proteomics to characterise allergen profiles in five commonly consumed shrimp species under raw and heat-treated conditions. Protein extracts (n = 3 per species/treatment) were analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) following in-solution digestion. Identified proteins were mapped against curated allergen databases and species-specific transcriptomes to assess presence and relative abundance. Complementary SDS-PAGE and immunoblot analyses using allergen-specific antibodies were performed to evaluate qualitative detection across species and treatments. Proteomic analysis revealed marked interspecies variability in allergen presence and abundance. Several allergens exhibited differential stability following heat treatment, reflecting distinct biophysical properties influencing persistence in heat-processed foods. Selected putative allergens identified by transcriptome analysis, including aldolase and enolase, were confirmed at the protein level, while others were not detected. Moreover, weak concordance between transcriptomic and proteomic abundance was observed for multiple allergens, including arginine kinase and myosin light chain. Immunoblotting for tropomyosin and myosin light chain demonstrated inconsistent detection across species and treatments, highlighting limitations of antibody-based detection systems. These findings establish that shrimp allergen composition is species- and heat processing-dependent, with implications for risk assessment frameworks. Quantitative proteomics provides a robust platform for comprehensive allergen profiling and supports improved detection strategies for aquatic food safety.