Effects of different heat treatment methods on Tan lamb flavor: An integrated approach with GC × GC-TOF-MS, GC-IMS, Lipidomics, and multispectral techniques

This study investigated the effects of three heat treatment methods (steaming, roasting, and stir-frying) on changes in protein conformation, flavor profiles, and lipid components of Tan lamb meat. The results showed that stir-frying promoted the oxidation of lipids and proteins most significantly, followed by roasting, while steaming resulted in the lowest oxidation level. This phenomenon was attributed to differences in heating temperatures, heat transfer efficiencies, oxygen exposure, and the degree of heat-induced dehydration. A total of 217 volatile flavor compounds (VFCs) were identified using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOF-MS). Through multivariate statistical analysis combined with odor activity value (OAV) analysis, 1-octen-3-ol, (E,E)-2,4-decadienal, octanal, and (Z)-4-decenal were determined as key VFCs. Pearson correlation analysis revealed significant correlations between these key VFCs and changes in protein conformation. Furthermore, lipidomic analysis of Tan lamb samples subjected to different heat treatment methods revealed that the differential lipids were mainly glycerophospholipids (GPs) and glycerolipids (GLs). Among these, triglyceride (TG) 18:1_18:1_18:1 and lysophosphatidylcholine (LPC) 19:1 were identified as potential biomarkers for monitoring the extent of thermal processing and predicting lamb flavor formation. This study contributes to the in-depth elucidation of the underlying mechanisms of flavor variation in Tan lamb under diverse heat treatment methods.