Hot-pressed flaxseed oil is favored in Northwest China as cooking oil due to its flavor and oxidative stability. The mechanism of enhancing oxidation stability of hot-pressed flaxseed oil by neoformed Maillard reaction products (MRPs) remains mysterious. Maillard model reaction between phosphatidylethanolamine (PE) and reducing sugar of flaxseed, glucose (Glu)/fructose (Fru)/xylose (Xyl), was conducted to investigate the antioxidant characteristics of products. MRPs of PE-Xyl had a superior reactivity and anti-oxidative capabilities, which could improve the oxidative stability of flaxseed oil and inhibited the formation of aldehydes in the accelerated oxidation. Phosphatidylethanolamine-linked pyrrolecarbaldehyde (PLP) was the main antioxidant component in MRPs of Xyl-PE by MS and NMR analysis and verification of antioxidant activity. Furthermore, the results of quantum chemical calculation show that the antioxidant activity center of PLP is the pyrrole group. The findings of this study provide insights into the chemical basis underlying the improved oxidative stability of hot-pressed oils.
This study examines the antioxidant capacity of linusorb (LOs) and their interaction with phospholipids (PLs) in hot-pressed flaxseed oil (HO), which is valued for its enhanced oxidative stability in Northwest China. Utilizing antioxidant assays and molecular simulations, the research aims to: 1) Assess oxidation indices to identify optimal roasting conditions and monitor LOs during the oxidation of HO, triacylglycerol (TAG), and TAG + LOs; 2) Analyze the oxidation kinetics of crude LOs (cLOs) from cold-pressed oil (CO) and LOs (hLOs) from HO in the presence of PLs; and 3) Molecular dynamics simulations to explore the interactions between PLs and LOs. The findings indicate that HO exhibits superior oxidative stability due to a higher concentration of LOs and PLs, with altered the antioxidative behavior of LOs. Simulation suggests that PLs can bind to LOs, facilitating their migration to the water-oil interface and enhancing their antioxidant effects.