The structural modification of pea protein concentrate with gum Arabic by controlled Maillard reaction enhances its functional properties and flavor attributes

Abstract

The aim of this research was to investigate the impact of conjugation with gum Arabic (GA) on the functional properties and flavor profile of pea protein concentrate (PPC). The PPC-GA conjugates was prepared by incubating the mixture at a mass ratio of 1:4 at 60 °C and 79% relative humidity with variable times (0, 1, 3, and 5 days). The grafting of GA to PPC was confirmed using SDS-PAGE and Fourier transform infrared-attenuated total reflection spectra. The degree of conjugation between PPC and GA over the course of incubation was determined by non-specific Maillard reaction markers, the loss of free amino groups, and color development. The results suggested that the solubility and emulsification properties of PPC-GA conjugates was remarkably improved after 3 days incubation and further extending incubation time deteriorated the functionalities. Surface morphology modifications of the conjugates revealed by scanning electron microscope may explain the enhanced functionality. The corn oil-in-water emulsions stabilized by PPC-GA conjugates of 3 days incubation also showed great physical stabilities against pH (2–8), thermal processing (25, 37, and 72 °C), and ionic strength (0, 100, 300, and 500 mM), as compared to PPC alone or the mixture of PPC and GA. HS-SPME-GC-MS analysis and quantification of beany flavor markers in PPC-GA conjugates indicated that the beany flavors markers were remarkably diminished after 1 day incubation. The findings from this study indicated that controlled Maillard reaction could be an effective strategy to not only enhance the functionality of poor water soluble plant proteins, but also mitigate the overwhelming beany flavors, thus promoting the utilization of plant proteins as functional ingredients in food industry.