Multi-omics analysis of lipids and aroma compounds in beef under grain-fed and grass-fed production methods

Different production methods for grain-fed and grass-fed cattle affect beef quality and flavor, yet systematic studies on aroma profile differences and the reasons underlying these variations remain limited. This study employed multi-omics analysis to characterize the aroma and lipid profile in grain-fed and grass-fed beef, as well as to identify key lipid molecules and biological pathways linked to aroma formation. Multi-omics analysis revealed that triglycerides (TG (16:0_14:1_18:1), TG (16:0_16:0_18:1), TG (16:0_16:1_18:1), TG (16:0_18:1_18:1), TG (16:0_18:1_18:2), and TG (18:0_16:1_18:1) et al.), diacylglycerols (DG (16:0_18:1) and DG (18:1_18:1)), and free fatty acids (FA (16:1), FA (18:1), FA (18:2), FA (20:3), and FA (20:4)) molecules containing C14:1, C16:1, C18:1, C18:2, C20:3, and C20:4 fatty chains may serve as key precursors to drive distinct aromas in grain-fed and grass-fed beef. These processes are implicated in triglyceride metabolism and fatty acid metabolism pathways and are potentially regulated by DEGs in the PPAR signaling pathway. Specifically, <i>APOA</i> mediates triglyceride transport via lipoprotein secretion, while <i>SLC27A6</i> enhances intracellular lipid content by promoting long-chain fatty acid uptake. Our results provide a comprehensive understanding of the aroma characteristics and lipid profiles, establishing a theoretical basis for improving beef quality in both grain-fed and grass-fed production methods.