Effect of yam (Dioscorea spp.) starch on the physicochemical, rheological, and sensory properties of yogurt

Abstract

This study investigated the effect of the addition of starch from “hawthorn” yam (Dioscorea rotundata) and “creole” yam (Dioscorea alata) at different concentrations (0.1%, 0.3%, and 0.5% w/w) on the physicochemical and sensory properties of stirred-type yogurt. Pectin (0.3% w/w) was used as a reference stabilizer. Yogurt with yam starch presented 13.38% less syneresis than yogurts with pectin. At the sensory level, the most accepted treatment was yogurt with “creole” yam starch at 0.1% w/w. During 21 days of storage, yogurt with yam starch (“creole” and “hawthorn”) at 0.1% w/w showed a decrease in syneresis between 7% and 8%, while in those with pectin, syneresis remained practically constant in this period. Yogurt with yam starch was characterized as a pseudoplastic fluid, with a lactic acid bacterial count according to NTC 805. Yam starch can be used as stabilizer because it improves the physicochemical, sensory, and rheological characteristics of stirred-type yogurt. Especially the “creole” yam starch (0.1% w/w), which presents the best preference by consumers.