Optimized preparation and antioxidant activity of glucose-lysine Maillard reaction products

Reductive substances in Maillard reaction products (MRPs) improve the oxidative stability of food. This study explored the antioxidant activity of the main components of MRPs in glucose-lysine (GL) models. The optimal conditions for preparing the Maillard reaction (MR) were studied by a response surface methodology using FRAP as an evaluation index. The antioxidant activities, including ABTS, DPPH, and FRAP assays were determined. The MRPs obtained from gel chromatography purification were subjected to UV absorbance and fluorescence intensity determined, and MRPs with antioxidant activity were detected by HPLC-MS. The results showed that optimal conditions were at a reaction temperature of 110 °C, a reaction time of 120 min, an initial of pH 10, and n (Glc: Lys) = 1:1. MR intermediates, browning pigments, and fluorescent compounds were related to antioxidant activity. Pearson correlation analysis further confirmed that the content of the main components (m/z 309) was significantly positively correlated with the antioxidant activity of MRPs.