The effect of non-standard heat treatment of sheep's milk on physico-chemical properties, sensory characteristics, and the bacterial viability of classical and probiotic yogurt

•Non-standard sheep's milk heat treatment for the production of yogurt was used.•Classical yogurt and probiotic yoghurt were produced.•The yogurts showed high content of nutritionally important whey proteins.•Both kinds of yoghurt presented acceptable sensory evaluation.

Classical and probiotic set yogurt were made using non-standard heat treatment of sheep's milk at 60 °C/5 min. Physico-chemical properties, sensory characteristics, and the viability of bacteria that originated from cultures in classical and probiotic yogurt were analysed during 21 days of storage at 4 °C. For the production of yogurt, a standard yogurt culture and a probiotic strain Lactobacillus rhamnosus GG were used. At the end of storage time of the classical and probiotic yogurt the totals of non-denatured whey proteins were 92.31 and 91.03%. The viability of yogurt culture bacteria and Lactobacillus rhamnosus GG were higher than 106 cfu/g. The total sensory score (maximum - 20) was 18.49 for the classical and 18.53 for the probiotic. In nutritional and functional terms it is possible to produce classical and probiotic sheep's milk yogurt by using a non-standard temperature of heat treatment with a shelf life of 21 days.