Lactic acid bacteria have probiotics potential which help to prevent and treat a variety of medical disorders and have significant nutritional value when used in fermented foods. This study was designed with the objective of isolation and characterization of Lactic acid-producing bacteria with potential probiotic properties from milk and commercialized yogurt samples, after encapsulated in alginate beads and evaluating potential in yogurt formation. To enhance the viability of isolated strains encapsulation with sodium alginate was done. For this study, 40 samples (20 milk, 20 yogurts) were taken from different areas of Multan, Punjab. Method: The 20 different isolated strains were treated for the selection of the best bacteria with the probiotic potential to survive in harsh conditions i.e. at low pH, in the presence of bile salt, gastric juice stimulant, and have the ability to produce bacteriocin. Antibacterial activity, Antioxidant test, and detection of virulence factor test were performed. Further probiotic yogurt was prepared using isolated lactobacillus and yeast strains as inoculum. Different parameters were observed, including fermentation time, pH, microbiological analysis, total solid content, water holding capacity, and synergies at different time intervals. Results: In this study, isolated Lactobacillus strains had promising probiotic characteristics they were able to tolerate acidic pH, could survive at compatible temperatures intestinal tract, were able to tolerate bile salts presence, and could have biofilm formation and bacteriocin production. Probiotic yogurt showed its microbial count increases during 4 weeks and was higher in the case of alginate beads. Similarly, total solid content increases and decreases in the case of beads. Conclusion: All the strains have the best probiotic properties and are used for yogurt formation. Which plays a significant role in a variety of fermentation processes. They ferment carbohydrates that exist in food.

Keywords: LAB, Encapsulation, Bacteriocin, Fermentation