Comparative study of physicochemical, nutritional and functional properties of whole and defatted legume flours

Abstract

The physicochemical, functional and nutritional properties of whole and defatted legume flours in five types of legumes [kidney bean (Phaseolus vulgaris), mung bean (Vigna radiata), pigeon pea (Cajanus cajan), soybean and black soybean (Glycine max)] were determined. Ash, protein and carbohydrate contents in defatted legume flours were higher than in whole legume flours. Bulk density (BD), water adsorption index (WAI) and water solubility index (WSI) of whole and defatted legume flours ranged from 0.43 g/mL - 0.92 g/mL, 2.04 g/g – 5.01 g/g and 20.67 g/100 g – 46.93 g/100 g, respectively. The water and oil absorption capacity of defatted black soybean flour and defatted soybean flour had improved (p<0.05) after the oil extraction process. Defatted legume flours exhibited higher emulsifying activity (EA) compared to whole legume flours (p<0.05), but lower emulsifying stability (ES) which ranged from 88.90% - 94.92% and 94.32% - 99.08%, respectively. Flour concentrations at 5 g/100 mL showed the highest foaming capacity (FC), with reduced foaming stability (FS) across time. Pearson correlation coefficient revealed a protein had significant relationship between physicochemical and functional properties of whole and defatted legume flours. The Pearson correlation coefficient revealed that protein positively correlated with most physicochemical and functional properties of whole and defatted legume flours, while carbohydrate only had a strong positive correlation with BD and WAI.