Physical and Functional Properties of Flour from Three Varieties of Yam in Taraba State

Yam (Dioscorea spp.) is a dietary staple and economically significant crop in Nigeria's North East geopolitical zone, yet systematic characterisation of the flour properties of locally cultivated varieties remains incomplete. This study evaluates the physical and functional properties of flours produced from three yam varieties, specifically Dioscorea rotundata (White yam), Dioscorea cayenensis (Yellow yam), and Dioscorea alata (Water yam), cultivated in Wukari, Taraba State. Yam flour was prepared by peeling, slicing, drying at 65 degrees Celsius, milling, and sieving to 250 micrometres. Physical properties measured included bulk density, particle size distribution, colour, and water activity. Functional properties determined were water absorption capacity, oil absorption capacity, swelling power, solubility, gelation concentration, and foam capacity. Results showed significant varietal differences in all measured parameters. Dioscorea rotundata flour exhibited the highest water absorption capacity and gelation capacity, making it most suitable for paste-based applications. Dioscorea alata demonstrated superior swelling power and solubility, suggesting suitability for soup thickeners and extrusion applications. The study contributes to the characterisation of underutilised yam varieties for food product development and draws on recent literature on indigenous starch sources in West Africa. Findings are relevant to food processors, the Taraba State Agricultural Development Programme, and food engineering researchers focused on root and tuber crop utilisation. Keywords: yam flour, functional properties, Dioscorea, varieties, Taraba State