The yogurt production and consumption has grown significantly in recent years due to increasing consumer awareness of its effects on health. Reducing the fat percentage in low-fat yogurts can affect the product characteristics, so finding a formulation that can compensate for the effects of fat reduction while maintaining sensory characteristics is of great importance. In this study, the effect of microbial transglutaminase enzyme at two levels (0 and 0.02% w/v) and replacing oat extract with milk at four levels (0, 10, 20, and 30% v/v) on the physicochemical properties and overall acceptance of synbiotic yogurt during storage was investigated. The results showed that the use of this enzyme significantly increased the pH and reduced the acidity and syneresis of the yogurt (p<0.01) compared to the control sample, but had no effect on the dry matter content of the samples. Also, with increasing percentage of oat extract, the acidity and dry matter of yogurt increased and the pH of the samples decreased significantly (p<0.01). Also, with the passage of storage time, pH and water content decreased and acidity increased significantly (p<0.001), while, like the enzyme, the storage time variable did not have a significant effect on the dry matter of yogurt. Sensory results showed that, unlike the transglutaminase enzyme, increasing the percentage of oat extract caused a decrease in the overall acceptance score of the product, but no significant difference was observed in this regard between the control sample with yogurt samples containing 10 and 20 percent of barley extract. Therefore, according to the results of the study, in order to produce functional yogurt, transglutaminase enzymatic treatment (0.02 percent) and the use of 20 percent oat extract in the product formulation are recommended.