Effects of buffer additives and thermal processing methods on the solubility of shrimp (Penaeus monodon) proteins and the immunoreactivity of its major allergen

• Protein solubility of heated shrimp increased in buffer with DTT and Tween-20.
• Shrimp processed by dry heat had higher soluble protein than those of wet heat.
• Autoclaving denatured shrimp tropomyosin.
• Tropomyosin from autoclaved shrimp had a lower IgE binding.
• Common shrimp cooking methods did not reduce the IgE binding of tropomyosin.

This study examines the potential of two buffer additives (Tween 20 and DTT) to improve the solubility of proteins from shrimp subjected to different heat treatments and the allergenicity of tropomyosin in the extracts. The concentration of soluble proteins extracted by all the buffers from processed shrimp was significantly reduced compared with untreated samples. The concentration of total soluble proteins from heat treated shrimp increased significantly when phosphate buffer containing both surfactant and reducing agent was used as the extraction buffer. However, the concentrations of heat-stable proteins in the buffers were mostly similar. The electrophoretic profile of extracted proteins showed that tropomyosin is very stable under the different heat treatment methods used in this study except for high pressure steaming where the intensity of tropomyosin band was reduced. Competitive inhibition ELISA showed that high pressure steaming reduced the allergenicity of tropomyosin compared with other heat treatments methods.