Physicochemical, Rheological, and Sensory Characteristics of Yogurt Fermented by Lactic Acid Bacteria with Probiotic Potential and Bioprotective Properties

The applicability of two lactic acid bacterial strains with probiotic potential and bioprotective properties as additions in the starter culture in yogurt fermentation was examined. The studied strains, Lactobacillus delbrueckii subsp. bulgaricus KZM 2-11-3 and Lactiplantibacillus plantarum KC 5-12, inhibited the growth of Kluyveromyces lactis, Kluyveromyces marxianus, and Saccharomyces cerevisiae. The strain L. delbrueckii subsp. bulgaricus KZM 2-11-3 directly inhibited Escherichia coli. The important characteristics for the quality of the yogurt product, such as physicochemical parameters during fermentation and storage, rheological characteristics, and sensory changes during the storage of samples were determined. The yogurt samples with the strains did not differ in most parameters from the control yogurt with the commercial starter. The added strains showed stable viability in the yogurt samples during storage. The yogurt sample with L. delbrueckii subsp. bulgaricus KZM 2-11-3 and the sample with both strains based on the total evaluation were very similar to the control yogurt with the commercial starter. Using these strains as probiotic supplements to enrich the starter cultures in yogurt production will contribute to developing new products with benefits to human health.