Variation in the functional properties of blends of heat-treated local thickening seeds and cocoyam flour

Abstract

The effects of pre-milling heat treatment types on the functional properties of the resultant flour blends of some indigenous thickening seeds and cocoyam (ede-ocha) at various percentages were examined. Flours of indigenous thickening seeds of achi, ofo and ukpo, and that of cocoyam were used in this work. Functional analyses showed that the blend type of ofo-cocoyam flour had better swelling index (SI) (3.28±0.28) and water absorption capacity (WAC) (5.10±1.77ml/g) than that of ukpo-cocoyam; ukpo-cocoyam blend exhibited better oil absorption capacity (OAC) (1.41±0.21ml/g), though not significantly higher than ofo-cocoyam and achi-cocoyam (p≤0.05). Among treatment types, flour of boiled sample had better SI (3.35±0.60) and WAC (4.56±1.58ml/g) than that of the roasted sample which gave better OAC (1.45±0.33ml/g) that was statistically equal to boiled blend (1.39±0.23ml/g), steamed blend (1.26±0.27ml/g) and raw blend (1.44±0.29ml/g). Among blending ratios, 25% cocoyam (CY) flour blend had significantly higher WAC (5.07±0.62ml/g) than the control and other blends, with SI of 3.06±0.59 which statistically equal to the 75% cocoyam flour blend (3.12±0.53). The boiled sample exhibited better functional properties than others; such that ofo-CY exhibited better functional properties than other blends types as the 25% CY flour sample exhibited better functional properties than other blend ratio samples. Further work should be directed to investigate this experiment with another species of cocoyam to check whether remarkable improvements can be obtained in the characteristics of the resultant flour blend with achi, ofo, ukpo.