Thermal stress alters the allergen and proteome profile of the redclaw crayfish (Cherax quadicarinatus)

Rising global temperatures and growing demand for sustainable protein are concurrent challenges driving the expansion of aquaculture, including farming of shellfish such as the Australian Redclaw Crayfish (Cherax quadricarinatus). Although environmental stressors alter animal physiology, their effects on food protein allergenicity remain unexplored, particularly in shellfish, a leading cause of food-induced anaphylaxis. This study investigated how rearing temperature affects protein and allergen expression in redclaw reared at either 17 °C, 28 °C, or 32 °C. Raw and cooked protein extracts were analysed using SDS-PAGE and immunoblotting with crustacean-allergic individuals (n = 19). Whole extracts were examined by liquid-chromatography mass spectrometry (LC-MS) to identify and quantify proteins, assess differential expression, and perform gene ontology (GO) analysis across temperatures. Significant temperature-dependent variation in protein and allergen profiles was observed. IgE-binding intensity increased at 17 °C and decreased at 32 °C in raw and cooked extracts, indicating increased allergenicity under cold-stress. At 17 °C, allergens including heat shock protein 70 (HSP70) and fatty acid-binding protein (FABP) were upregulated, alongside GO categories related to protein folding and metabolic/catabolic processes (e.g., triosephosphate isomerase (TPI), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), enolase, and fructose-bisphosphate aldolase (FBA)). GO expression profiles between 28 °C and 32 °C were largely similar. Allergens tropomyosin (TM), myosin light chain (MLC), and troponin C (TnC) were unchanged across temperatures. Environmental temperature alters the allergen/protein profiles of redclaw and clinically relevant IgE-antibody reactivity. These findings highlight the impact of environmental and farming conditions when assessing food allergen exposure risks in a changing climate and highlight the need for further validation in other aquaculture species.