Evaluation of the possible technological uses of some dioscoreas tubers: name congo (Dioscorea bulbifera) and mapuey (Dioscorea trifida).

A comparison between the chemical composition and physical characteristics of flame congo (Dioscorea bulbifera) and mapuey (Dioscorea trifida)white an d purple varieties. was made. The tubers were evaluated for their physical attributes (morphology, size and weight). The chemical analysis was done ac cording to AOAC methods (1990) and the pasting properties of the flours wer e evaluated using the Brabender Viscoamilograph. The mapuey tubers have an elongated shape, with one end wider while name congo presents a rounded sha pe. The results of the chemical analysis show that mapuey tubers have more proteins content (p less than or equal to0.05) than either purple mapuey tu bers purple or name congo tubers. The flours overall viscosity, measured st the same concentration, was higher for white mapuey varieties. The gelatin ization temperature range was similar among the flours. The negative breakd own datas suggest that the flours viscosity increases during the gelatiniza tion process of all flours. Neither suspensions showed a viscosity peak. Se t-back and consistency were lower in the name congo flour. The absence of a viscosity peak and the high temperature stability of the name congo flour make it an ideal ingredient for instant soup mixes. The flours high viscosi ty level developed by white and purple mapuey varieties should make it a su itable sauces thickener.