Fast screening of chicken egg lysozyme in white wine products by extractive electrospray ionization mass spectrometry

Fast detection of trace lysozyme, one of the most important food allergens in white wine samples, was achieved by extractive electrospray ionization mass spectrometry without sample pretreatment in this study. The multiply-charged ions of m/z 1587 were chosen for the quantitative detection of lysozyme in white wine, showing linear dynamic signal responses in a range of 5-75 μg/mL with a linearity coefficient of 0.999 and an acceptable relative standard deviation(RSD) of 8.0%-15.0% for directly measuring lysozyme in the complex food samples. The limit of detection for lysozyme in white wine sample was calculated to be 5 μg/mL, which was lower than the amounts that can provoke allergic reactions(oral test with 3 mg or labial test with 1 mg/mL). A single sample analysis was completed within 1 min. The data demonstrate that extractive electrospray ionization mass spectrometry is a useful tool for fast screening lysozyme in the complex matrix, showing promising application in the rapid detection of food allergen.