Motahare Boughani - M.Sc. Student, Department of Food Science and Technology, College of Agriculture, Varamin-Pishva Branch, Islamic Azad University, Varamin, Iran
Rezvan Pourahmad - Department of Food Science and Technology, , College of Agriculture, Varamin-Pishva Branch, Islamic Azad University, Varamin, Iran
Ali Akbarian Moghari - Department of Food Science, Technology and Engineering, Faculty of Agricultural Engineering and Technology, Tehran University, Karaj, Iran

Background and Aim:Due to the occurrence and spread of various diseases, the use of functional food, because of having health effects, seems to be more necessary. The purpose of this study was to investigate the effect of oligofructose on viability of Bifidobacterium lactis and sensory properties in synbiotic yogurt.Methods:t. The amounts of 3 and 5 percent of oligofructose were used in probiotic yogurt containing Bifidobacterium lactis. The viability of probiotic bacteria and sensory properties of synbiotic yogurt were investigated at intervals of 1, 11 and 21 days.Results: Compared to control sample (without oligofructose), the viability of probiotic bacteria of test samples increased significantly (p <0.05). The number of probiotic bacteria decreased significantly during storage time (p <0.05) but population of probiotic bacteria in all treatments was higher than the minimum required for health effects.According to the result of this research sensory scores (odor, texture, and overall acceptance) of the samples increased significantly (p <0.05). However, teste of the majority of samples did not change significantly (p > 0.05). The sample containing 3% oligofructose had the highest sensory score (overall acceptance) which also had a high population of probiotic bacteria (3 × 106 cfu/ml) at the end of the maintenance period.Conclusion:Therefore, it can be said that the compound of prebiotic with a positive effect on survival of probiotic bacteria in symbiotic yoghurt samples can improve the health properties of probiotic product.

synbiotic yogurt, oligofructose, Bifidobacterium lactis, sensory properties