Characterization of lipids in Guangdong small-ear spotted pig and their crossbreeds during cold storage revealed by LC–MS-based method

Cold storage is a common storage and transportation method for pork, and the change of lipid molecules in meat during cold storage is an important factor affecting the quality of meat. In this study, liquid chromatography-mass spectrometry (LC-MS) was employed to analyze and compare the lipid changes and differences in the longissimus dorsi of DuHei pig (Duroc×Yihao Black pig, DH), Duhua pig (Duroc×Guangdong small-ear spotted pig, Dh), and Guangdong small-ear spotted pig (HZ) at 45 minutes, 1 day, 3 days, and 7 days during cold storage (4℃). A total of 1993, 2071, and 1719 lipid molecules were identified from DH, Dh, and HZ, respectively. The longissimus dorsi of DH, Dh, and HZ exhibited similar characteristics in overall lipid composition , with the top 10 lipid subclasses enriched in TG , PC , PE , Hex1Cer, Cer , MePC, DG , CL , SM , and dMePE. During cold storage, the differential lipid subclasses were predominantly enriched in TG, PC , and PE. Phosphatidylethanolamine (PE) containing C16:0/C16:1 demonstrated a significant increase in relative abundance after 3 days, suggesting its potential as an indicator of the duration of meat cold storage and a biomarker for assessing the freshness meat products. The changes in relative abundance, structural characteristics, and functional enrichment analysis of differential lipids indicated that DH may possess superior storage stability compared to Dh and HZ. This study offers new insights into the molecular changes of lipids in Chinese indigenous and hybrid pig pork during cold storage. • First study on lipid profiles of Chinese local pig breeds during cold storage. • Systematic study of lipid types and changes in three pig breeds under cold storage. • PE with C16:0/C16:1 as a potential biomarker for meat freshness and storage time. • Research provides a basis for optimizing pork cold storage technology.