Quality evaluation of yoghurt stabilized with sweet potato (Ipomoea batatas) and taro (Colocassia esculenta) starch

Abstract

Stabilizers are important component in manufactured products such as yoghurt. The addition of stabilizers improves body, texture, appearance, mouth feel and prevents technical defects such as synersis in yoghurts. In this study starch was extracted from plant sources (sweet potato, taro) with and without use of chemicals. Yoghurt was enriched with different levels of extracted starch. Yoghurt samples were analyzed for physicochemical and functional attributes such as pH, acidity, synersis, water holding capacity, viscosity, total solids and sensory profile. Use of chemically extracted starches at the level of 0.3-0.4% (Sweet potato) and 0.2-0.3% (Taro)   in yoghurt manufacturing showed better  results  in  terms  of  lowering synersis, increasing water holding capacity, viscosity and overall acceptability as compared to the yoghurt containing stabilizer i.e. gelatin 0.5% w/w. Use of starches did not significantly affect the sensory attributes. Yoghurt that contains sweet potato and taro starch at 0.5% gave excellent results for water holding capacity, viscosity and for all sensory attributes as compared to gelatin