Comparison of nutritional and functional properties of mung bean (Vigna radiate) and cowpea (Vignaunguiculata) protein isolates processed by isoelectric precipitation

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Dairy, wheat and soy arc the most derive form of protein isolates and these are widely used in the food industry. The aim of this study was to extract and characterise legume protein isolates from Ion-fat legume seeds (Mung bean and cowpea). In this purpose, extracted protein isolates were compared with commercially available soy protein isolate to determine their potential usage in food applications. The isoelectric precipitation method was followed at pH of 4.5. Both protein isolate recovery(22.20±0.46 g / KlOg) and protein yield (73.87±1.53%) were higher in mung bean protein isolate (MPI) as compared to cowpea protein isolate (CPI), i. e, 20.81±0.20 g / IllOg and 68.89±0.66% respectively. The values for protein contents in legume protein isolates significantly differ (j> < 0.05) from each other and higher amount (92.99±0.30%) in MPI followed by commercial SI’l (90.98±0.32%) and CPI (89.00±0.53%) respectively. In the proximate composition of MPI, fat, fibre, ash and •carbohydrate contents (on dry weight basis) were found to be 0.72±0.08%, 0.18:1:0.04%, 0.99±0.03% and 5.03%, respectively while CPI the same composition was found to be 0.81±0.05%, 0.22±0.0I%, l.I5±0.II% and 8.72%. Results were compared with the commercially available soy protein isolate (SPI) with respect to the fat (0.43±0.02%), fibre (0.18±0.05%), ash (4.52±0.02%) and carbohydrate (3.89%) content in dry weight basis. Assessed functional properties of SPI exhibit high protein solubility, high water and oil -absorption..capacity than the MPI and CPI. Protein isolates from mung bean appeared to have the best gelling property.