Functional properties of milk proteins as affected by Maillard reaction induced oligomerisation

Abstract Milk proteins were modified by Maillard reaction with glucose, lactose, pectin and dextran and analysed for changes in molar mass distribution and functional properties. The study revealed that oligomeric (20,000–200,000 g/mol) and polymeric (>200,000 g/mol) Maillard reaction products with heterogeneous functional property profiles were generated. Compared to untreated milk proteins, milk protein/saccharide Maillard products formed highly viscous solutions and performed increased antioxidant capacity. Improved heat stability was detected for milk protein/dextran products, higher surface hydrophobicity for milk protein/glucose and milk protein/lactose products, and increased overrun for milk protein/pectin and milk protein/dextran products. Total milk protein/saccharide Maillard products formed outstandingly stable protein foams, Maillard products of total milk protein and glucose, lactose or pectin stable O/W-emulsions. Milk protein/pectin and milk protein/dextran Maillard products were characterized by increased emulsifying activity, and whey protein/saccharide products by enhanced pancreatic in vitro digestibility. The study characterizes Maillard reaction products of milk proteins and makes it possible to specifically select modified proteins for industrial applications according to the requirements towards food proteins, weighing changes in techno- and tropho-functional protein properties.