Influence of convective hot air drying on physico-functional, thermo-pasting and antioxidant properties of elephant foot yam powder (Amorphophallus paeoniifolius).

Abstract

The present study focused on the effect of different drying temperatures (40, 50, 60 and 70°C) and combination of pre-treatments: potassium metabisulphite (KMS), potassium metabisulphite + Citric acid + blanching (KCB)] on functional, thermo-pasting and antioxidant properties of elephant foot yam (EFY) powder. Drying temperature and pretreatment reduces the water and oil absorption capacity, and the highest values were 2.34g/g and 1.19g/g for drying at 40°C for the untreated sample, respectively. KMS pretreatment enhanced the bulk density, foaming capacity, emulsion capacity, and emulsion stability with an increase in drying temperature. Pasting temperature and viscosity decreased with an increase in drying temperature, and the maximum was observed at 40°C for KMS pretreatment. Blanching increases the gelatinization temperature resulting in higher mid-and end-temperatures for KCB pretreatment. The antioxidant properties decreased with an increase in the drying temperature and were found to be minimal in the case of KCB treated samples.