Antioxidant activities and emulsification properties of the new model systems of whey proteins and reduced sugars

The final products formed from the various systems of the Maillard reactions possess different functional properties such as browning intensity, antioxidant activity, and emulsion stability. To study these properties and activities, different systems of whey proteins reaction with glucose and fructose at different concentrations to form a new model system of Maillard reaction products (MRPs) was observed. Results showed that high optical densities (peaks) at 280 and 420 nm indicated the formation of the intermediate stages of MRPs and the formation of advanced MRPs, respectively. Additionally, results showed that these Maillard reaction model systems possessed different antioxidant activities as demonstrated by DPPH and reducing power assays (20 - 93.2% and 40 - 90%, respectively) depending on the type and concentration of sugar, and the incubation time. The whey protein-fructose model system possessed high antioxidant activity (93.2%), and had the highest percentage on the emulsion stability index (75.4%). The whey protein-fructose model systems comprised the highest number of the studied model systems to form MRPs, and had highly powerful antioxidant activity and emulsifying index.