Phospholipidomics and quantum chemistry calculation unravel the changes in phospholipid molecules of flaxseed oil during roasting

• ►Phospholipidomic analysis method and quantum chemistry calculation were employed. • ►70 phospholipid molecules were identified in raw and roasted flaxseed oils. • ►Each categories of phospholipid molecules exhibited different chemical changes. • ►PE was more stable than PC according to the model reaction system and DFT. • ► The reduction of PE in flaxseed oil was due to the Maillard reaction. Roasting flaxseed significantly improves the antioxidant activities and flavor of its oil; however, the effect of roasting on phospholipid molecules in flaxseed oil is limited. Herein, on the basis of phospholipidomics and quantum chemistry calculation, phospholipidome in raw, light, and dark roasted flaxseed oils and their changes were systematically explored and compared. Seventy individual phospholipid molecules were detected in raw and roasted flaxseed oils. After light roasting, major classes of phospholipid molecules including phosphatidylethanolamine, phosphatidylcholine, and phosphatidylinositol increased 11.43-, 36.62-, and 67.88-fold, respectively. PE exhibited 92.06% reduction after dark roasting. The model reaction showed that the main reaction of PE was the Maillard reaction during roasting. Quantum chemistry calculation demonstrated that the reaction energy barriers of the Maillard reaction (96.81 kJ/mol) was much lower than the hydrolysis (188.84 kJ/mol) for PE. The study is expected to provide new insight into the change mechanism of PE during flaxseed processing.