Effects of fermented feed on lipid composition and flavor of pasteurized egg yolks: A promising approach for flavor-enhanced liquid duck eggs

This study investigated the effect of fermented feed on the lipid composition and volatile flavor compounds of pasteurized duck egg yolks using comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry and lipidomics. Fermented feed significantly reduced off-odor intensity of egg yolks, as confirmed by sensory evaluation, compared to the control group. Ninety-four volatile compounds were identified, with thirty-two showing significant differences between the two groups ( p  < 0.05). Key volatile compounds (acetophenone, toluene, and 1-octen-3-ol) were upregulated, while undecanal was downregulated. These four key compounds were closely associated with flavor alterations. Lipidomics enrichment analysis revealed eight significantly altered lipid categories, including elevated levels of polyunsaturated fatty acid-rich lipids, such as triglyceride (18:2/14:3/20:4), phosphatidylethanolamine (18:1e/20:4), and lysophosphatidylcholine (22:4), which were positively correlated with desirable aroma compounds. These findings offer a theoretical foundation for enhancing the flavor quality of pasteurized duck egg products and developing high-quality liquid duck egg products.