Effect of inulin on physico-chemical, microbial and sensory properties of the kefir produced of buffalo milk

Kefir is a fermented dairy drink that are produced using kefir grain and has beneficial effects on human health. In this study, the effects of the addition of Inulin (0.5, 1, 1.5%) on the physicochemical (pH, acidity, viscosity, syneresis and color), microbial (lactic acid bacteria and yeast) and organoleptic characteristics of kefir prepared with buffalo milk were investigated during 15 days refrigerator storage. The results showed that with increase of inulin content, the acidity and viscosity of kefir samples increased during storage period, while with increasing inulin content, the syneresis of the samples decreased on the last day of storage. Inulin also increased the number of lactic acid bacteria in kefir, indicating that the inulin was a prebiotic, but did not affect yeast growth. In addition, inulin reduced the lightness of kefir. Sensory evaluation results showed that inulin reduced the odor, taste and texture and had a negative effect on the overall acceptance of samples. According to the findings of this study, although inulin increased the probiotic properties of kefir, it had a negative effect on syneresis and sensory attributes of kefir.