Preliminary characterization of Yunnan dry-cured beef using lipidomics and volatilomics

Yunnan dry-cured beef is highly regarded for its unique aroma, but the mechanisms underlying its aroma formation remain unclear. In this study, GC-MS, GC-IMS, and UHPLC-QE-MS techniques were employed to analyze dynamic changes in fatty acids (FAs), volatile compounds, and lipids during the processing of Yunnan dry-cured beef, to preliminarily characterize the potential mechanisms underlying aroma evolution. The results demonstrated that the degree of lipid oxidation (POV and TBARS) increased significantly (P < 0.05) during the processing of Yunnan dry-cured beef, while moisture content and water activity decreased significantly (P < 0.05), and protein and fat contents increased significantly (P < 0.05). A total of 48 fatty acids were identified, with unsaturated fatty acids as the predominant class. These were further categorized into 16 saturated fatty acids (SFA), 18 monounsaturated fatty acids (MUFA), and 14 polyunsaturated fatty acids (PUFA). Volatilomic analysis identified a total of 13 aroma compounds. Among these compounds, ethyl acetate, ethanol-D, 1-propanol-D, 2-butanone, and 2-butanol-D exhibited the highest relative abundances at the end of processing, and these compounds are of great significance for the formation of the characteristic aroma of dry-cured beef. Lipidomic profiling identified 2418 lipids. Phosphatidylcholine (PC), triacylglycerol (TG), and phosphatidylethanolamine (PE) accounted for a high proportion and represented the major lipids involved in lipid metabolism and aroma formation. This study is the first to preliminarily characterize the lipid-mediated aroma formation mechanisms in Yunnan dry-cured beef, providing a theoretical and technical basis for processing optimization and quality improvement.