Rheological, sensorial and volatile profiles of synbiotic kefirs produced from cow and goat milk containing varied probiotics in combination with fructooligosaccharide

Lactobacillus acidophilus La-5 and Bifidobacterium bifidum Bb-11 accompanied with fructooligosaccharide (FOS) were used individually to develop a synbiotic kefir from cow and goat milk. Influence of milk type, as well as the probiotic strain was evaluated on the physicochemical, rheological, sensory, volatile flavor properties and probiotic viabilities of kefirs during 28d of storage. The results of this study highlight, L. acidophilus in combination with FOS had a supportive effect on the content of acetaldehyde, probiotics viability and overall sensory appreciation of samples at the end of storage. Particularly, cow milk kefir produced with Lb. acidophilus was found to be more effective on acetaldehyde formation (17.4 ppm mean value). Furthermore, cow milk favored the sensory properties of kefirs than goat milk. In conclusion, cow milk kefir supplemented with Lb. acidophilus and FOS was more appreciated. With regard to probiotic counts and rheological properties, while goat milk supported the survival of probiotics, cow milk had a positive effect on consistency index of samples. Therefore, these ingredients which could be used to provide synbiotic effect in kefirs could be preferred according to the targeted feature to meet the customer satisfaction by enhancing the aspects of products such as rheology, flavor and probiotic content.