Mechanism of Alfalfa in Enhancing Goose Egg Yolk Flavor: An Analysis Based on Metabolomics and Quantitative Lipidomics

ABSTRACT Organic egg production requires daily provision of coarse feed, fresh or dried forage, and silage to poultry. This study employed flavoromics, metabolomics, and quantitative lipidomics to investigate the effects of replacing 0% (CK), 10% (T10), and 20% (T20) of the basal diet of laying geese with alfalfa (Medicago sativa L.) on the sensory characteristics, flavor compounds, and flavor precursors of goose egg yolks. The results demonstrated that as the proportion of alfalfa increased, the overall odor intensity, flavor richness, and color saturation of the egg yolks were enhanced, with the T20 group achieving the highest overall sensory acceptance. A total of 28 key flavor compounds (odor activity value > 10) were identified, among which 2‐methyltetrahydrofuran‐3‐one contributed most significantly to the overall flavor profile. Notably, compared to the CK group, the concentrations of characteristic volatile compounds (2‐pentylfuran and 1‐octen‐3‐ol) were significantly increased ( p < 0.05) in the T20 group. Integrated non‐targeted metabolomics and quantitative lipidomics analyses revealed the underlying mechanism: alfalfa supplementation increased the content of triglycerides containing linoleic acid and linolenic acid structures in the egg yolks. These lipid molecules facilitated the formation of 2‐pentylfuran and 1‐octen‐3‐ol flavors during lipid oxidation, thereby enhancing the flavor profile of the yolk. Furthermore, alfalfa supplementation effectively improved yolk color, resulting in superior sensory quality. These findings provide molecular‐level theoretical support for regulating goose egg quality through dietary intervention.