Utilization of chickpea protein isolate and Persian gum for microencapsulation of licorice root extract towards its incorporation into functional foods

Abstract This study aimed at the fabrication of licorice extract (LE)-loaded microparticles by complex coacervation, using chickpea protein isolate (CPI) and soluble fraction of Persian gum (SFPG). The LE-loaded microparticles with the highest encapsulation efficiency (97.87%) and loading capacity (11.35%) were obtained at pH 3 and CPI: SFPG ratio, core: coating ratio, and polymer concentration of 2, 1.5, and 2, respectively. The LE-loaded microparticles (2-15 μm) possessed heterogeneous microstructure, and the Fourier-transform infrared spectroscopy data confirmed the pronounced effect of electrostatic interactions and hydrogen bonding. The thermostability, amorphous structure, and color of the LE-loaded microparticles were significantly enhanced, compared to free LE. The sensory evaluation of the model beverages containing LE-loaded microparticles revealed microencapsulation was able to mask the bitter aftertaste and color of the extract. Thus, the results of this research confirm the potential of CPI-SFPG complex coacervates for the efficient delivery of glycyrrhizin via incorporation into functional food products.