Lipidomics and GC-MS Analysis of Key Lipids Involved in Forming Volatile Flavor Compounds in Longissimus Dorsi Muscles of Sheep

Abstract

The flavor of meat significantly influences consumers’ purchasing decisions, with lipids playing a crucial role as precursors in the formation of volatile flavors. In this study, we analyzed the lipids and volatile flavor substances in the longissimus dorsi muscles of Chaka (CK), Black Tibetan (BT), and Oula (OL) sheep by liquid chromatography–electrospray ionization mass spectrometry (LC-ESI-MS/MS) and gas chromatography-mass spectrometry (GC-MS) techniques. The results showed that the phospholipids PI (13:1_18:1), PI (16:0_16:0), PI (18:0_18:2), PE (18:0_18:3), PE (18:0_20:5), PE (18:1_18:3), PC (13:0_18:0), PC (14:0_18:2), PC (14:0_18:3), and PC (15:0_16:0) were related to the formation of the flavor substances (1.alpha.,4a.beta.,8a.alpha.)-1,2,3,4,4a,5,6,8a-octahydro-7-methyl-4-methylene-1-(1-methylethyl)-Naphthalene and.gamma.-Muurolene imparted spicy, herbal and woody sensory properties. The triglycerides TG (10:0_16:0_18:2), TG (12:0_16:0_18:2) and TG (12:0_16:1_18:2) were associated with the formation of acetic acid, 2-phenylethyl ester and benzenepropanoic acid, methyl ester, which gave the sheep floral, fruity, honey, balsamic, wine, rose and tropical sensory properties. The lipids Carnitine C10:0, Cer (d16:1/24:1), Cer (d18:1/22:1), Cer (d18:1/23:1), and PE (17:0–22:5) were connected to the formation of propylcyclohexane, which provided sheep with sweet, cooked, buttery and meaty sensory characteristics. This study offers insights into the mechanisms of flavor formation in sheep and lays a scientific foundation for the future evaluation and improvement of flavor in different sheep breeds.