Effects of different ohmic heating treatments on parvalbumin structure and reduction of allergenicity in Japanese eel (Anguilla japonica)

•Pure ohmic heating reduces processing time and energy consumption.•Ohmic heating did not alter parvalbumin’s molecular weight.•Ohmic heating effectively reduces parvalbumin allergenicity. We investigated the effects of ohmic heating (OH) on the structural properties and allergenicity of parvalbumin (PV). Compared to other heating methods (water bath heating (WH), OH combined with WH, and OH combined with air thermostatic heating (AH)), pure OH heating expended the least time and total energy. PV sensitization was reduced by approximately 65% by pure OH heating. SDS-PAGE, tricine–SDS-PAGE, and western blotting analyses revealed a molecular weight of sensitized β-PV of about 12 kDa. Band intensity decreased with increasing OH time, and significant changes were observed in amino acid content, secondary structure, microstructure, and dielectric properties. Reducing PV, allergenicity through protein unfolding and secondary structural changes, thereby possibly reducing the allergenicity of eel, provides a theoretical basis for developing hypoallergenic products.