Development of a liquid chromatography-tandem mass spectrometry method for simultaneous quantification of hen’s egg white allergens Gal d 1–4 in fresh and processed eggs

•An LC-MS/MS method was developed for simultaneous quantification of Gal d 1–4.•The limit of quantification was Gal d 1: 39.1 ng/mL, and Gal d 2–4: 9.77 ng/mL.•High reproducibility, sensitivity, and accuracy were confirmed for this method.•The Gal d 1–4 levels in egg foods were accurately determined with high specificity.•This method may provide reliable Gal d 1–4 level data for food and clinical fields.