Lipid remodeling is associated with aroma formation during thermal processing of quail egg yolk: an integrated...

Thermal processing substantially influences egg flavor quality, yet the metabolic basis underlying aroma development in quail egg yolk remains incompletely understood. In this study, GC-IMS, HS-SPME-GC-MS, lipidomics, and widely targeted metabolomics were integrated to characterize flavor-related metabolic changes during thermal processing. GC-IMS detected 48 VOCs, whereas HS-SPME-GC-MS detected 451 volatile features, of which 161 compounds with available odor threshold data were further evaluated by OAV analysis. Aldehydes, ketones, esters, and terpenoids predominated in cooked yolks. GC-IMS characterized the volatile fingerprint associated with thermal processing, whereas HS-SPME-GC-MS identified benzeneacetaldehyde and decanal as candidate odor-active compounds. Lipidomic analysis revealed extensive remodeling of glycerophospholipids and glycerolipids during heating, accompanied by marked alterations in amino acids, organic acids, and sugar derivatives. Differential metabolites annotated to fatty acid metabolism, α-linolenic acid metabolism, and pentose and glucuronate interconversions were associated with changes in volatile profiles. Multi-omics integration further revealed coordinated associations among lipid remodeling, changes in water-soluble metabolites, and aroma-associated VOCs. In particular, changes in glycerophospholipid species were closely correlated with aldehydes and other characteristic volatiles, highlighting a potential association between phospholipid remodeling and aroma development during thermal processing. Collectively, these findings provide an integrated metabolic perspective on aroma formation in cooked quail egg yolk and provide a basis for understanding the associations between lipid remodeling and volatile evolution during thermal processing.