Integrating flavoromics and multi-omics to reveal biomarkers of flavor characteristics in egg yolks.

Egg yolk flavor is a critical factor influencing consumer purchasing decisions and eating experiences, and it is gradually becoming an important dimension in the egg quality evaluation system. To investigate the functional molecules regulating egg yolk flavor change, we conducted flavoromics and multi-omics analyses on egg yolks from Bashang Long-tail Chickens (BL), White Leghorn Chickens (WL), and their hybrid offspring (WB). Six key volatile organic compounds (VOCs) were identified as significantly contributing to egg yolk flavor. Metabolic profiling revealed that lipids and lipid-like molecules, and organoheterocyclic compounds are the dominant categories of yolk metabolites. The associated lipid profile noted the regulatory role of linoleic acid in egg yolk metabolism. The constructed lipid-metabolite-flavor association network shows that LPG(16:1)/LPE(16:1)-13(S)-HODE-ethanol, 2-ethoxy-, PC(14:0_18:1)/LPE(16:1)/PE(18:0_16:1)-LysoPC(18:1(11Z))-1-pentanol and LPI(22:6)-PC(22:5)-1-pentanol are biomarkers that shape the flavor of different varieties of egg yolks. The research results provide important information for the systematic understanding of the flavor composition of BL, WL, and WB egg yolks, and provide a theoretical basis for egg flavor quality regulation and variety selection.