title: Extractability, stability, and allergenicity of egg white proteins in differently heat-processed foods.
abstract: Hen's egg white protein is a major cause of food allergy, and a considerable number of countries have introduced labeling directions for processed food products. To control compliance with these regulations, analytical assays for the detection of egg in manufactured foods have been developed. In this study, we have tested the performance of 3 commercially available kits for quantitative egg analysis using 6 model heat-processed foods. The 3 assays worked well under standard conditions with soluble egg white proteins, but only the kit using a denaturing-reducing extraction buffer detected egg in complex heat-treated food matrixes. The differently extracted food samples were further used to evaluate the stability and allergenicity of the egg white allergens ovalbumin, ovomucoid, ovotransferrin, and lysozyme with polyclonal anti-egg antibodies and sera of 6 patients with egg allergy. It could be shown that differences in egg protein extractability have a significant impact on the interpretation of study results.
authors.affiliation: National Veterinary Institute, Section of Chemistry, P.O. Box 8156 dep, N-0033 Oslo, Norway. christiane.faste@vetinst.no
authors.forename: Christiane K
authors.initials: CK
authors.lastname: Faeste
authors.forename: Kjersti E
authors.initials: KE
authors.lastname: Løvberg
authors.forename: Helene
authors.initials: H
authors.lastname: Lindvik
authors.forename: Eliann
authors.initials: E
authors.lastname: Egaas
mesh_terms: D000818:Animals; D002138:Calibration; D002645:Chickens; D003207:Conalbumin / Q000737:chemistry*; D004527:Egg Proteins / Q000032:analysis* / Q000737:chemistry; D004529:Egg White; D004797:Enzyme-Linked Immunosorbent Assay; D005519:Food Preservation; D006801:Humans; D007118:Immunoassay / Q000379:methods; D009113:Muramidase / Q000737:chemistry*; D010047:Ovalbumin / Q000737:chemistry*; D010059:Ovomucin / Q000737:chemistry*; D015203:Reproducibility of Results; D012987:Soil
chemical_list: D004527:Egg Proteins; D012987:Soil; D003207:Conalbumin; D010059:Ovomucin; D010047:Ovalbumin; D009113:Muramidase