Characteristics and antioxidant activity of Maillard reaction products from α-lactalbumin and 2′-fucosyllactose

The characteristics and antioxidant activity of Maillard reaction products (MRPs) from 2′-fucosyllactose (2′-FL), a human milk oligosaccharide, and α-lactalbumin (α-LA) were investigated. MRPs were prepared by reacting 2′-FL with α-LA at 60 °C and 79% relative humidity for up to 72 h. The absorbance and fluorescence intensity of heated α-LA-2′-FL increased as the heating time increased, while the free amino group content decreased, confirming that 2′-FL reacted with α-LA and produced various MRPs at different incubation stages. Conjugates of 2′-FL and α-LA and aggregation of α-LA were observed by SDS-PAGE. The secondary structure of α-LA did not change significantly after reacting with 2′-FL. In terms of antioxidant activity, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity and reducing power of α-LA-2′-FL increased significantly when compared with the protein only sample ( p  < 0.05). The findings provide a foundation for the characterization and functional analysis of MRPs in dairy products.