The viability of probiotic monoculture and quality of goat's and cow's bioyogurt

Bio-yogurts are obtained from milk of various ruminant species (most often cow and goat) and are a rich source of a variety of valuable nutritional compounds and probiotic microorganisms. The objective of the study was to assess the quality of fermented goat's and cow's milk containing probiotic monocultures during refrigerated storage (5 +/- 1 degrees C). Bio-yogurts were produced from raw material obtained from Saanen goats and Holstein Friesian Black and White cows, both kept on the organics farms. Four experimental products were produced: two from goat's milk: KBJ-L811 (with the YE-L811 yogurt starter culture and probiotics: L. acidophilus LA-5 and B. animalis subsp. lactis BB-12) and KBJ-X16 (the YC-X16 yogurt culture, LA-5 and BB-12) and two analogical cow's milk variants: BJ-L811 and BJ-X16. The products underwent microbiological, physicochemical, textural and sensory evaluation. The study confirmed that the activity of yogurt and probiotic cultures in goat's and cow's products was similar. In the case of yogurt cultures, their viability was min. 8 log (cfu/g). The count of probiotic bacteria was 7.7-8.4 log (cfu/g) for Bifidobacterium sp. and 5.9-7.4 log (cfu/g) for L. acidophilus. Although the yogurt cultures did not differ in their composition of bacteria species, the resulting products showed varied quality properties.