Maillard reaction products as functional components in oil-in-water emulsions: A review highlighting interfacial and antioxidant properties

Background: Lipid oxidation gives rise to the formation of off-flavors and is therefore a major concern for food quality. When present in food emulsions (e.g., milk, yogurts, salad dressings), labile polyunsaturated lipids usually oxidize faster than in bulk oil, which can be mitigated by antioxidants. However, the use of synthetic antioxidants is not desired from a “clean-label” point of view. Therefore, we focus on the potential of Maillard reaction products (MRPs), which are biobased molecules that are formed during heating, and of which some may possess excellent antioxidant and emulsifying properties. Scope and approach: The in situ antioxidant activity of MRPs in emulsion systems is reviewed; effects occurring in the continuous phase and at the interface of oil-in-water (O/W) emulsions are distinguished. A dedicated section of the review focuses on the MRPs that are intrinsically present in various foods. Key findings and conclusions: MRPs may partition between the continuous phase and the oil-water interface in emulsions, which allows them to counteract lipid oxidation by various physicochemical mechanisms, including metal chelation and free radical scavenging. MRPs intrinsically present in foods are promising components to achieve food products with high oxidative stability, while complying with consumer points of view.