ABSTRACT

Three varieties of water yam (Dioscorea alata) namely "Mbalaigum," "Umb 80" and "Ikogiri" were processed into flour. The samples were dried using sundrying, oven drying and foam-mat drying techniques. The resultant flour was evaluated for proximate and functional properties. It was also used for the production of cake, yam balls and chin-chin. The sensory characteristics of these products were also evaluated. The response surface analysis was employed in evaluating the effects of the interactions between the drying methods and water yam species on the properties studied. The results showed that at P<0.05 species affected the moisture content and crude fibre content. The drying process affected the foam stability only. The sensory scores showed that species had a significant effect on the taste of the water yam balls. The moisture content ranged between 6.00-11.10% (Ikogiri); 5.96-10.34% (Mbalaigum); 5.94-8.64% (Umb 80). The crude fibre content ranged between 2.16-3.82% (Ikogiri); 2.08- 3.08% (Umb 80); 1.00-1.42% (Mbalaigum). The foam stability ranged between 7.25-9.40% (foam-mat drying); 5.00-10.90% (sundrying); 0.00-6.05% (oven drying). The other chemical and functional properties were not significantly affected by species and drying treatment. Foam-mat drying was found to yield most preferred cake and balls. While sundrying yielded cake, ball and chin-chin that was better than products derived from ovendrying.