Traditional cooking methods decreased the allergenicity of egg proteins

Egg allergy is one of the most common food allergies globally. This study aimed to assess the impact of four traditional cooking methods on the allergenicity of egg proteins using a comprehensive strategy, including simulated gastrointestinal digestion in vitro, serology experiments, a rat basophilic leukemia (RBL)-2H3 cell degranulation model, and a passive cutaneous anaphylaxis (PCA) mice model, and the structure changes were detected by circular dichroism (CD) spectra and ultraviolet (UV) spectra. The results showed that the processed egg proteins were more readily digested compared to raw egg proteins. The serological experiments revealed a significant reduction in immunoglobulin E binding of egg proteins after thermal treatments (p < 0.05), particularly after frying. Subsequently, the RBL-2H3 cell degranulation experiment demonstrated a marked decrease in the level of egg allergens-induced β-hexosaminidase release after cooking (p < 0.05). Moreover, the results from the PCA mice model indicated that the increase in vascular permeability was effectively relieved in the treated groups, especially in frying group (p < 0.05). Additionally, the α-helix and β-turn contents of processed egg proteins were significantly decreased (p < 0.05) compared with native egg proteins. The UV spectra findings showed that all cooking treatments caused significant alterations in the tertiary structure, and fluorescence analysis indicated that cooking decreased the surface hydrophobicity of egg proteins. In conclusion, four traditional cooking methods reduced the allergenicity of egg proteins, particularly frying, and this reduction was associated with structural changes that could contribute to the destruction or masking of epitopes of egg allergens. PRACTICAL APPLICATION: Egg allergy has a serious impact on public health, and there is no ideal treatment method at present. This study demonstrated that four traditional cooking methods (boiling, steaming, baking, and frying) reduced the allergenicity of egg proteins, especially frying, and the results will provide a basis for the development of hypoallergenic egg products.