Extraction and evaluation of functional properties of groundnut protein concentrate

The effect of membrane processing on the functional properties, structural changes, subunit profile and sensory attributes of the groundnut protein concentrate was investigated. Results indicated an increase in the nitrogen solubility and foaming capacity of the protein concentrate over all pH ranges (2-10) compared to acid precipitated protein isolate. Protein concentrate showed higher emulsion stability index compared to control flour and protein isolate. Surface hydrophobicity studies showed that protein concentrate is less hydrophobic (~29 units) compared to acid precipitated protein isolate (~34 units). SDS-PAGE profile of the samples showed similarity in the subunit pattern of groundnut protein concentrate and groundnut flour. Sensory analysis suggested membrane filtration could reduce the groundnut-like nutty and beany notes of the concentrate. Thus, membrane technology could give a protein concentrate with improved functionality and sensory characteristics which will have potential application in the development of food product formulations.