Comparative evaluation of the nutrient composition and lipidomic profile of different parts of muscle in the Chaka sheep

we compared and analyzed the nutritional composition and volatile flavor substances in longissimus dorsi (LD), psoas major (PM), and biceps femoris (BF) of the Chaka sheep, and then analyzed the lipid composition using the lipidomics technique of UHPLC-Q-Exactive Orbitrap MS/MS. The results showed that the LD had the highest crude protein (CP) content (22.63%), the highest levels of aspartic acid (5.72%) and histidine (2.76%), the BF had the highest contents of glycine (3.40%) and Proline (2.88%), the PM had the highest abundance of ω-6 polyunsaturated fatty acids (PUFA) (7.06%), linoleic acid (C18:2n6c) (5.03%), and volatile flavor compounds (alcohols, ketones, and esters). Moreover, our study detected 2639 lipid molecules classified into 42 classes, among which phospholipids were the main lipids, accounting for nearly half of the total lipids. The differential analysis of the lipids showed that triacylglycerol (TG), diacylglycerol (DG), and monosaccharide ceramide (Hex1Cer) were the most abundant in PM. Phosphatidylserine (PS), phosphatidylethanolamine (PE), and phosphatidylcholine (PC) were the most prominent lipid molecules in BF. Phosphatidylinositol (PI), cardiolipid (CL), and sphingolipid (SM) were the most widespread lipid molecules in LD. Intermolecular correlations between PC, PE, Hex1Cer, PS, TG, DG, and CL were revealed by correlation analysis.