Keele Research Repository

Metabonomic profiling, using High Performance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry (HPLC-Q-ToF-MS), was adopted in this study to uncover differences in the small molecule profiles of egg yolks, between two sets of six eggs that were stored at 5°C and 23°C for five weeks. Choline, a compound that has previously been shown to have potential use as a biomarker of egg age, was observed to have a significantly lower abundance in the yolks of eggs that were stored at 5°C for five weeks compared to eggs stored at 23°C for the same length of time. A follow-up targeted study observed that the previously discovered trend of increasing choline concentration in egg yolk, with increasing egg age, is not repeatable when the eggs are stored at 5°C rather than 23°C. It concluded that, by refrigerating eggs at 5°C, the accurate prediction of egg age using choline as a biomarker can be prevented.