Influence of drying temperature on physico-chemical and techno-functional attributes of elephant foot yam (Amorphophallus paeoniifolius) var. Gajendra

Elephant foot yam is a salubrious but underutilized tuber. Being rich in starch as well as various bio-actives (phenolics), it offers dual-functionality. The study was undertaken to obtain Amorphophallus flour that can be utilized in various food applications. Pre-cooked Amorphophallus paste was dried in convective air dryer at varying temperatures (50, 60 and 70 °C) and milled into a powder. The powders were then analyzed for physico-chemical and techno-functional aspects. Drying temperature markedly affected the color, techno-functional attributes including pasting properties, phenolic content and anti-oxidative capacity of Amorphophallus powder; the oxalate content remained unaffected by drying temperature. Decrease in whiteness index and increase in browning index were noticed with rising drying temperature. All gelatinization-viscosity parameters (peak, trough, breakdown, final and setback viscosity) showed a decline with rising drying temperature while an increasing trend was observed for pasting temperature. Significant differences were also observed in flavor and mouth-feel (p<0.05) scores of Amorphophallus-milk dispersion and were maximum for powder obtained upon drying at 60 °C. The nutritional and thickening potential of yam could very well be utilized in hybrid-dairy foods.