Comprehensive study of Maillard induced structural modification of sesame (Sesamum indicum L.) protein isolate: characterization, functional and antioxidant properties

The utilization of sesame protein in food products is limited due to the various challenges posed by its functional properties. This study aimed to investigate the Maillard reaction between sesame protein isolate (SPI) and guar gum (GG) under wet-heating conditions (80 °C) and to evaluate the functional and antioxidant properties of prepared conjugates. The functional properties of the samples were analyzed by observing their solubility, emulsion activity, emulsion stability, foam capacity (FC), foam stability, and oil/water-holding capacity. ABTS and DPPH radical scavenging, reducing power, and iron chelating activity were used to analyze the antioxidant properties. FTIR, XRD, and fluorescence spectroscopic studies indicated that the secondary structure of the protein underwent extensive alterations. The functional properties of conjugates were highly improved by the structural changes caused by the Maillard reaction. Emulsion activity (up to1.8-fold), and FC (up to 61.67%) were improved. The antioxidant activity of conjugates was significantly greater than the unmodified protein, DPPH-RS assay (42.83% upper), ABTS-RS assay (up to 74%), reducing power (up to 2.78-fold), and iron chelating (up to 87.55%). This study demonstrates how the Maillard reaction can enhance sesame protein's functional and antioxidant characteristics.