Variations in the lipid of dry-cured mutton ham during storage: UPLC-MS-MS-based lipidomic analysis

Dry-cured mutton ham is prone to quality deterioration during storage due to excessive lipid oxidation. Therefore, to control the ham quality, it is essential to comprehensively understand the lipid changes occurring in the storage. In this study, the variations and primary metabolic pathways of ham lipids during storage were investigated utilizing the lipid metabolomics. A total of 579 lipids belonging to 21 subclasses were identified, involving 376 lipids with significant differences (P < 0.05, VIP > 1, FC > 2 or < 0.5). Glycerolipids were the most abundant of all lipids, and glycerophospholipids contained the highest number of subclasses. PCA and OPLS-DA of lipid metabolites revealed FFA(19:1), TG(14:0/18:0/18:3), TG(14:0/18:0/20:4), TG(14:0/20:0/20:4), TG(14:0/20:1/20:4), TG(16:0/16:0/22:5), TG(16:0/16:1/22:4), TG(18,1/18:3/20:2), and TG(18,2/18:3/20:2) emerged as the key contributors to differences in mutton ham quality during storage. Furthermore, the metabolism of glycerophospholipid and sphingolipid was the critical metabolic pathway during the storage of mutton ham.