Effect of Processing on the Proximate Composition of the Dehulled and Undehulled Mungbean [Vigna radiata (L.) Wilczek] Flours

Abstract

The effects of some processing treatments on the proximate composition of dehulled and undehulled mungbean seeds flours were investigated. The mungbean seeds were subjected to boiling , toasting and sprouting, at different intervals before milling into flour. The flour samples were analyzed for proximate composition using standard methods and the dehulled samples were found to possess better proximate compositions than the undehulled samples, except for crude fiber. Results showed that increase in boiling time (30, 45, 60 and 90 min) did not significantly (p>0.05) increase the moisture (10.30-10.65%) and carbohydrate (57.16-65.05%) contents but rather decreased the fat, ash, crude fiber and energy values. The undehulled mungbean boiled for 45 min had the highest crude protein (21.86%), the 30 min boiled sample had the highest fat content (2.20%), while the carbohydrate was highest (66.17%) in the 90min boiled sample. However, the dehulled sample boiled for 30 min had the highest crude protein (26.27%) and fat (2.27%), whereas the dehulled sample boiled for 90 min highest carbohydrate content (65.05%). The 30 min toasted sample had the highest crude protein (19.70%) while the 90 min toasted sample had the highest fat (2.43%) and carbohydrate (69.88%). However, the dehulled sample toasted for 30 min had the highest protein (24.52%) while the 90 min toasted sample had the highest fat (2.07%) and carbohydrate (71.99%). The undehulled sample sprouted for 72h had the highest crude protein (37.17%), while the 24 h sprouted sample had the highest fat (2.32%) and carbohydrate (49.08%). However, for the dehulled sample, increase in sprouting time (24-36 h) increased the moisture (10.43-10.69%) and crude protein (35.90- 36.50%) contents but reduced the fat (1.35-1.23%), fiber (2.90-2.83%), carbohydrate (49.02-47.88%) and energy values (351.83-348.59 kcal/g).