Electrohydrodynamic (EHD) –assisted extraction of protein from mung bean (Vigna radiate L.) sprout: Effect of solid to solvent ratio on the functional properties

Background & Aim: Mung bean knwn as a traditional food which has been used both as nutritional food and herbal medicine over 2000 years. Mung bean sprouts are one of the most commonly used bean sprouts and considered an as appropriate source for the extraction of highly valuable proteins. Experimental: In this study, the effect of different solid to solvent ratios (1:5, 1:10, 1:15 and 1:20 g/mL in electrohydrodynamic (EHD)-assisted extraction on the extraction yield and functional characteristics of sprouted mung bean protein isolate (SMPI) was evaluated. In addition, the structural and thermal properties of SMPI were investigated using Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC), respectively. Results: The highest protein extraction yield, protein solubility (PS), oil absorption capacity (OAC), foaming capacity (FC) and foaming stability (FS) were obtained in the solid to solvent ratio of 1:20 g/mL. The results of FTIR showed that in the solid to solvent ratio of 1:20, the α-helix structure in SMPI decreased and transformed to random coil structure, leading to increased protein solubility. According to the DSC analysis, the highest denaturation temperature and protein stability were attributed to the solid-to-solvent ratio of 1:20 due to higher water content. Recommended applications/industries: The present results indicated that EHD pretreatment with the solid to solvent ratio of 1:20 could improve the functional properties of SMPI and EHD-assisted extracted SMPI could be considered as a potential nutraceutical or ingredient of functional and health-promoting foods