Proximate Composition And Functional Properties Of Raw, Boiled And Fermented Water Yam (Dioscorea Alata)

ABSTRACT

Dioscorea alata (water yam) was evaluated in this study for the nutritional and ant-nutritional qualities by giving them three different treatments (blanching, boiling and fermenting). This study reveals the proximate composition, functional properties, ant-nutritional properties and mineral composition of water yam flour. The proximate composition are as follows: Moisture content (10.71%,12.80% and 11.82%) crude protein (8.65%, 6.87% and 8.72%) crude fiber (1.03%, 0.89% and 0.93%), ash content (4.23%, 4.61% and 4.80%) ether extract (0.67%, 0.68% and 0.63%) carbohydrate (85.43%, 87.05% and 84.95%). Functional properties includes: Water absorption capacity (2.52g/g, 2.40g/g and 3.11g/g), bulk density (0.6g/ml, 0.59g/ml and 0.58g/ml) oil absorption capacity (1.46g/g, 1.28g/g and 1.57g/g) swelling index (2.20%, 1.97% and 2.13%) gelatinization capacity ( 0.75%wt/vol, 0.75%wt/vol and 1.30%wt/vol) foam capacity (12.80%, 11.80% and 11.76%) foam stability (8.73%, 7.62% and 7.29%) emulsion capacity (19.90%, 18.73% and 19.74%) emulsion stability (13.64% 12.41% and 12.60%) pH (8.30%, 9.80% and 7.54%) temperature (26.20°c, 26.20°c and 26.20°c).Anti-nutritional factor reveals; Oxalate (0.85%, 0.20% and 0.51%) tannin (0.84%, 0.38% and 0.57%) phytate (0.76%, 0.15% and 0.36%).The mineral content calculated were calcium, magnesium and iron. Calcium (0.09mg/100g, 0.20mg/100g and 0.14mg/100g) magnesium (0.14mg/100g, 0.30mg/100g and 0.30mg/100g and iron (0.04mg/100g, 0.04mg/100g and 0.06mg/100g) respectively.