EFFECT OF YAM (DIOSCOREA ROTUNDATA) CULTIVAR ON PHYSICO-CHEMICAL PROPERTIES OF INSTANT YAM FLOUR

The effect of yam (Dioscorea rotundata) cultivar on the quality characteristics of instant yam flour was investigated. Three cultivars of white yam (Dioscorea rotundata), TDr 275 (efuru), TDr 90-1 (okunmado), and TDr 608 (alasinrin) were processed into instant yam flour and the flour was subjected to physico-chemical analysis using standard methods. Results obtained showed that the carbohydrate, protein and ash content of fresh yam tubers were greater than values obtained for their respective flour samples, while the crude fibre and fat content of instant yam flour samples were greater than the fresh yam tuber samples. In term of bulk density, water absorption capacity, starch solubility, swelling index and starch damage index, sample TDr 275 was highly rated followed by TDr 608 and TDr 90-1 respectively. Sample TDr 275 recorded the highest ratings for peak viscosity (199 RVU), final viscosity (223 RVU), breakdown viscosity (40 RVU), trough (172 RVU) and setback viscosity (66 RVU) followed by TDr 90 – 1 and TDr 608 respectively. TDr 90-1 exhibited the highest degree of whiteness (L*) and least degrees of redness (a*) and yellowness (b*) when compared with other samples. It was closely followed by samples TDr 608 and TDr 275 with no significant difference (P>0.05). Therefore, TDr 275 (efuru) can be considered as the most suitable for instant pounded yam flour production, followed by TDr 90-1 (okunmado) and TDr 608 (alasinrin) respectively