Physicochemical and functional properties of two cowpea cultivars grown in temperate Indian climate

Flours of two local cowpea cultivars namely Red cowpea and Black cowpea were analysed for proximate composition, pasting and functional properties. The crude protein and fat contents were higher for Black cultivar than the Red cultivar. The apparent amylose content was significantly higher for Red cowpea (25.54%) than Black cowpea (15.09%). Polyphenols were significantly higher for Red cowpea than Black cowpea. The pasting profile of two cultivars revealed significantly higher values of peak viscosity (1873 cP), setback viscosity (701.00 cP), breakdown viscosity (705.33 cP) and final viscosity (1868.67 cP) for Red cowpea than Black cowpea. Water absorption capacity and oil absorption capacity were found in the range of 1.22–1.39 g/g and 0.71–0.72 g/g, respectively, for the two cultivars. Emulsifying properties varied significantly between the two cultivars. Foaming capacity (198.67%) and foaming stability (84.85%) were significantly higher for Red cowpea than Black cowpea (73.81% and 75.43%). Swelling power was observed significantly higher for Black cowpea than Red cowpea at 90°C. Solubility index was also significantly higher for Black cowpea than Red cowpea throughout the temperature range.