Advances on the impact of thermal processing on structure and antigenicity of chicken ovomucoid

BACKGROUNDOvomucoid (OVM) is the dominant allergen found in egg white. The heat-induced changes on chicken OVM structure and antigenic properties were assessed at acidic, neutral and alkaline pH values. RESULTSThe fluorescence spectroscopy measurements indicated changes in the conformation of OVM caused by both pH and thermal treatment. The OVM molecule exhibited higher exposure of hydrophobic residues at 7.0, as indicated by the synchronous spectra, intrinsic fluorescence and quenching experiments. When heating the protein at pH9.5, the molecular structure appeared more compact. The antigenic properties of OVM, estimated through the enzyme-linked immunosorbent assay, appeared not to be sensitive to heat at pH7.0 and 4.5. Single molecule level investigations indicated that the secondary and tertiary structure of OVM was affected by the thermal treatment. CONCLUSIONSExperimental results indicated over 90% reduction of the antigenicity at pH9.5 and temperature of 100 degrees C. Significant changes of the linear epitopes exposure and location of the conformational epitopes were highlighted after performing heating molecular dynamics simulations of OVM from 25 degrees C to 100 degrees C. (c) 2017 Society of Chemical Industry