Effect of Toasting on the PhysicoChemical Compositions of Two Colour Variations of African Yam Beans (Sphenostylis stenocarpa)

ABSTRACT

 Two colour variation (Grey and Brown) African yam bean seeds were toasted for 5. 10, 15 and 20 minutes respectively, and used to study the effect of dry heat treatment on the anti nutrient and cooking time of African yam bean seeds. Toasting significantly reduced all the anti nutrient contents at (p<0.05). Alkaloid in the grey coloured beans ranged from 13.43mg/l00g to 16.37mg/100g while the tannin ranged from 7.97mg/l 00g to 17.97mg/l 00g. Oxalate in the grey coloured beans ranged from 0.43mg/l 00g to 0.82mg/1 00g while phytate ranged from 2.97mg/1 00g to 4.31 mg/I 00g. Hemagglutinin in the grey coloured beans ranged from 3.03Hu unit/g to 11.J0Hu unit/g while sapponin was not dictated. For the brown coloured African yam beans. the alkaloid content ranged from 12.0Jmg/l 00g to 17. 70mg/J 00g while tannin ranged from 8.77mg/100g to 18.27mg/ I 00g. Oxalate ranged from 0.53mg/J 00g to 0. 90mg/l 00g while phytate ranged 3.0 I mg/100g to 4.57mg/1 00g. Hemagglutinin ranged from 3.10Hu unit/g to 8.00I-lu unit/g while sapponin was not dictated. Toasting also reduced significantly at (p><0.05) the cooking time of the two beans. The cooking time of the grey coloured beans ranged from 5.94 hours to7.22 hours while brown coloured beans ranged from 5.94 hours to 6.32 hours. This implies that toasting could serve as a pre - processing method to reduce cooking time and eliminate most of the anti-nutritional factors in African yam beans other legumes. > Alkaloid in the grey coloured beans ranged from 13.43mg/l00g to 16.37mg/100g while the tannin ranged from 7.97mg/l 00g to 17.97mg/l 00g. Oxalate in the grey coloured beans ranged from 0.43mg/l 00g to 0.82mg/1 00g while phytate ranged from 2.97mg/1 00g to 4.31 mg/I 00g. Hemagglutinin in the grey coloured beans ranged from 3.03Hu unit/g to 11.J0Hu unit/g while sapponin was not dictated. For the brown coloured African yam beans. the alkaloid content ranged from 12.0Jmg/l 00g to 17. 70mg/J 00g while tannin ranged from 8.77mg/100g to 18.27mg/ I 00g. Oxalate ranged from 0.53mg/J 00g to 0. 90mg/l 00g while phytate ranged 3.0 I mg/100g to 4.57mg/1 00g. Hemagglutinin ranged from 3.10Hu unit/g to 8.00I-lu unit/g while sapponin was not dictated. Toasting also reduced significantly at the cooking time of the two beans. The cooking time of the grey coloured beans ranged from 5.94 hours to7.22 hours while brown coloured beans ranged from 5.94 hours to 6.32 hours. This implies that toasting could serve as a pre - processing method to reduce cooking time and eliminate most of the anti-nutritional factors in African yam beans other legumes.