Sensory Properties of Bulgarian Yogurts, Supplemented with Lactobacilli as Probiotic Adjuncts

Dairy products supplemented with probiotic cultures are a widely accepted approach in the development of functional foods. Moreover, this is the easier way to administrate and to deliver a probiotic culture to the consumers. With this aim, four potential probiotic strains, belonging to the species Lactobacillus plantarum, Lactobacillus salivarius, Lactobacillus brevis and Lactobacillus delbrueckii subsp. bulgaricus were preselected as probiotic adjuncts to Bulgarian yogurt. The sensory properties of fermented products, enriched with these cultures, were evaluated using descriptive analyses. The tests were conducted to establish the differences between probiotic and standard yogurts and to estimate the technological relevance of preselected strains. At the end of the storage period, a high ratio of survival and strain-specific effects on sensory quality of the obtained fermented milks were detected with greater influence on the flavor/taste. The L.plantarum was estimated as the most appropriate adjunct, with a positive effect on sensory properties of typical Bulgarian yogurt. Practical Applications Functional foods, incorporating probiotic bacteria with scientifically proven health claims, have a great potential for improving the healthy balance and the quality of life. Currently they provide the largest segment of the functional food market. Thus, the search for new probiotics is in continuous great interest today. With this aim we pre-selected four Lactobacilli in vitro characterized as candidate probiotics. The technological relevance of these lactic acid bacteria cultures as probiotic adjuncts to Bulgarian yogurts is very important for their further industrial implementation. The key parameters, Lactobacillus viability in fermented milks and the impact of the probiotic adjuncts on the sensory quality, were monitored. Obtained results suggest perspectives for an application of the strain L. plantarumRL as adjunct culture in dairy products like yogurt. The other studied strains, L. salivariusLS and L. brevisKR could be used as probiotics in other types of fermented dairy products and functional foods.