Abstract

Characterization of three varieties of brown cowpeas (Vigna unguiculata) grown in Nigeria

Author(s): Ijeoma Osuji, Florence O.Uruakpa, Uduak Ekot

Protein-rich cowpea grain is widely consumed in Nigeria where it is commonly known as “beans” with different varietal names. Composition of seed variety and the identification of its functional properties are essential in determining uses for cowpea flours in food formulation. This study characterized three lesser known varieties of brown cowpea grain grown in different regions in Nigeria based on their physical and functional properties. Three brown cowpea (white-eyed, firmly attached testa) varieties namely Akidi, Akidi Elu and Nkoti Iwang (26.02%, 25.46% and 24.90% protein, respectively) were assessed using standard methods. Swelling index of the flour was obtained as a ratio of volume occupied by sample after and before swelling.Water and oil absorption capacities of the flour were measured and result was expressed as g oil or water absorbed/g sample. Results show that average seed weight of Akidi Elu (0.12g) was higher than that ofAkidi (0.10g) and Nkoti Iwang (0.11g). Bulk density, water absorption, oil absorption, swelling index and viscosity of the three cowpea flour fractions were significantly affected by their location (P<0.05). Bulk density ranged from0.63 to 0.80 g/mLwithAkidi Elu and Nkoti Iwang having higher values thanAkidi.Water absorption ofAkidi Elu (1.95 g H20/g) and Akidi (2.00 g H20/g) were statistically different from that of Nkoti Iwang (1.42 gH20/g) flour.Brown cowpea flour can find application in food supplementation and as functional ingredient in various formulated foods.