Evaluation of gum arabic from Acacia senegal var kerensis and Acacia senegal var senegal as a stabilizer in low-fat yoghurt

Abstract

Gum arabic is a dried, gummy exudate obtained from the stems and branches of Acacia senegal and Acacia seyal. In Kenya, gum arabic comes from Acacia senegal var kerensis although its exploitation for commercial and industrial application is marginal. Therefore, the aim of this study was to characterize and determine the effect of the gum from A. senegal var kerensis on the quality characteristics of set low-fat yoghurt compared to gum arabic from A. senegal var senegal, with a view to increasing its utilization locally. Yoghurt was prepared containing gum arabic at four concentrations (0.2%, 0.4%, 0.6%, 0.8% gum w/v).  Results showed that A. senegal var kerensis gum had higher molecular weight and gelling properties compared to A. senegal var senegal gum. In addition, A. senegal var kerensis gum was less susceptible to syneresis and showed a higher absolute viscosity compared to A. senegal var senegal gum at all concentration levels. Sensory evaluation revealed that addition of gum arabic significantly improved the body and the texture of the yoghurt. Therefore, A. senegal var kerensis gum is a better yoghurt stabilizer than gum arabic from A. senegal var senegal. An optimal gum concentration of 0.6% of A. senegal var kerensis gum in low-fat yoghurt is recommended from the results of this study.