A study on structural, functional properties and allergenicity of β‐lactoglobulin by malondialdehyde during milk processing

β-;actoglobulin (βLG) is the main component of milk. Milk βLG is highly susceptible to lipid peroxidation during processing and preservation. Notably, malondialdehyde (MDA) is one of the main lipid peroxidation products, which could influence the structure, functional properties and allergenicity of βLG. In the present study, the structure of different samples was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, fluorescence spectroscopy, circular dichroism, and liquid chromatography-tanndem mass spectrometry. Functional properties were determined by foaming and emulsifying properties. Allergenicity was assayed by cell and animal models. The results revealed that MDA induced changes in the structural profile of βLG. The special amino acids, lysine, histidine, arginine, glycine and phenylalanine were modified. These structural changes of βLG influence foaming and emulsifying properties. Furthermore, KU812 cell results showed that the release of histamine and β-hexosaminidase decreased by 55.6% and 43.3% with 20 mm MDA treatment, respectively. The BALB/c mouse model showed that the MDA-βLG group had decreased levels of antibodies, histamine and mMCP-1 in sera. Notably, the allergenicity was substantially reduced by promoting Th1-related cytokines and suppressing Th2-related cytokines. The present study has revealed that MDA treatment induced changes in the functional and allergic properties during milk processing. © 2025 Society of Chemical Industry.