In Food chemistry
Free-range eggs are ethically desirable but as with all high-value commercial products, the establishment of provenance can be problematic. Here, we compared a simple one-step isopropanol method to a two-step methyl-tert-butyl ether method for extracting lipid species in chicken egg yolks before liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The isopropanol method extracted 937 lipid species from 20 major lipid subclasses with high reproducibility (CV < 30 %). Machine learning techniques could differentiate conventional cage, barn, and free-range eggs using an external test dataset with an accuracy of 0.94, 0.82, and 0.82, respectively. Lipid species that differentiated cage eggs were predominantly phosphocholines and phosphoethanolamines whilst the free-range egg lipidomes were dominated by acylglycerides with up to three fatty acids. The lipid profiles were found to be characteristic of the cage, barns, and free-range eggs. The lipidomic analysis together with the statistical modeling approach thus provides an efficient tool for verifying the provenance of conventional chicken eggs.
Chin Sung-Tong, Hoerlendsberger Gerhard, Wong Kok Wai, Li Sirui, Bong Sze How, Whiley Luke, Wist Julien, Masuda Reika, Greeff Johan, Holmes Elaine, Nicholson Jeremy K, Loo Ruey Leng
2022-Dec-30
Authenticity, Chemometrics, Eggs, Lipidomics, Machine learning, Ultra performance liquid chromatography-mass spectrometry
