Effect of sucrose replacement with rebaudioside A and isomalt on viability of probiotic bacteria and physicochemical and sensory properties of kefir ice cream

Kefir ice cream is a fermented dairy dessert made using kefir in the formulation of ice cream. The objective of this study was to produce kefir ice cream by use of low- calorie sweeteners including Rebaudioside A and isomalt in place of sucrose. Treatments A (control, only sugar), B (4 % isomalt and 10 % Rebaudioside A), C (6% isomalt and 20% Rebaudioside A), D (8% isomalt and 30% Rebaudioside A) and E (10% isomalt and 40% Rebaudioside A) were evaluated for physicochemical and sensory properties as well as probiotic bacteria count on 1, 30, 60 and 90 d. The results showed that by adding stevia and isomalt, acidity, viscosity and probiotic bacteria count significantly increased while pH and over run significantly decreased (P< 0.05). During storage, the viability of probiotic bacteria, pH and over run significantly decreased while acidity and viscosity significantly increased (P<0.05). Scores of flavor and total acceptance for treatments D and E were lower than those of other samples. Treatment C (6% isomalt and 20% Rebaudioside A) was selected as the superior one because in addition to having more desirable physicochemical characteristics compared to control sample, it showed no significant difference from control in sensory total acceptance and its probiotic bacteria count was higher than the limit recommended by International Dariy Federation (106 CFU/g).