Component-specific interaction between egg ovalbumin and edible oil fume particles in Chinese cooking: conformational remodeling drives changes in digestibility and allergenicity.
Abstract
Interactions between food processing-derived components and food proteins can markedly alter protein conformation and functional properties. Among them, cooking oil fume particles (COFPs) are widespread contaminants from high-temperature Chinese cooking. This study first compared the effects of COFPs from four common edible oils (rapeseed, RCOFPs; soybean, SCOFPs; corn, CCOFPs; and lard, LCOFPs) on the OVA structure and function. Physicochemical assays showed that all COFPs triggered OVA aggregation (particle size increased from 0.48 to 896.86 nm) and reduced zeta potential, driving an ordered secondary structure remodeling with distinct component-specific patterns. RCOFPs enriched in polycyclic aromatic hydrocarbons (especially fluoranthene, stably binding OVA at -7.9 kcal mol-1 through hydrophobic bonds) may be related to β-sheet enrichment, which directly promoted allergenic epitope exposure and resulted in enhanced IgE/IgG binding and KU812 cell degranulation. High-peroxide LCOFPs promoted disulfide bond formation and α-helix elevation, inducing compact conformational remodeling that enhanced OVA's gastrointestinal digestion resistance. Pearson analysis revealed a potential structure-function relationship. Soybean oil and corn oil exhibited weaker effects on the nutritional functionality of OVA than the other tested oils under the present experimental conditions. These findings clarify the regulatory effects of thermal processing contaminants on the health-related properties of food proteins, providing scientific guidance for the selection of edible oil in Chinese cooking and the nutritional and safety control of thermally processed egg products.