Lipid molecule profiling in Lentinula edodes during hot air drying via untargeted lipidomics: Composition, dynamic variations and contribution to characteristic flavor

The dynamic changes in lipid molecular species composition and contents in Lentinula edodes during hot air drying were analyzed by untargeted lipidomics through ultra-high-performance liquid chromatography-Q Exactive HF-X Orbitrap Mass Spectrometer, and their contribution to the characteristic aroma formation in Lentinula edodes during hot air drying was investigated. Seventy-six lipid molecular species were identified, including glycerolipids, glycerolphospholipids, lysoglycerophospholipids, and fatty acids. Triglyceride (86.33 %) and fatty acid (10.96 %) were the major lipid subspecies in fresh Lentinula edodes , showing remarkable variations during hot air drying. Phosphatidylcholine 18:2_18:2, phosphatidylethanolamine 18:2_18:2, phosphatidylethanolamine 16:0_18:2, triglyceride 18:2_18:2_18:2, triglyceride 16:0_18:2_18:2, linoleic acid, and linolenic acid were identified as the potential differential lipid molecular species during hot air drying. The verification experiments confirmed that 1-octene-3-ol could be produced by linoleic acid and linolenic acid, with enzyme activity playing a crucial role. The dose-effect relationships were best described by S-type BiDoseResp and Allometricl fitting curves in Lentinula edodes matrix without and with inactivated enzymes, respectively. Furthermore, this study systematically tracked the lipid transformation and content variations in Lentinula edodes during hot air drying and explored the potential role of lipid molecular species in aroma formation, especially 1-octene-3-ol. It would provide a scientific approach to elucidate lipid profiles in Lentinula edodes and offer new insights for flavor quality control in heat-processed edible fungi.