Evaluation of probiotic properties of lactic acid bacteria isolated from sheep milk and its suitability as a starter in a milk‐cereal‐based beverage
Kamalesh Kumar Meena, Manvik Joshi, Pallavi Rao, N. L. Panwar, Lokesh Gupta, Sunil Kumar Meena
Abstract
Abstract Probiotics are live beneficial bacteria that improve health when given to a host in sufficient quantities. This research explored the possible probiotic attributes of amylase‐producing lactic acid bacteria (ALAB) from sheep milk. Five strains out of 76 isolates were found to be amylase‐producing LAB that were characterized by morphological, phenotyping, and biochemical tests, and identified by 16S rRNA sequencing and phylogenetic evaluation. These strains were characterized for probiotic attributes such as tolerance to bile salt and acid, resistance to lysozyme and phenol, antioxidative activity, simulated gastric and pancreatic digestion, and cell surface properties (auto‐aggregation, cell surface hydrophobicity, and adhesion to Caco‐2 cells). Additionally, tests for antimicrobial activity (antifungal and antibacterial) and safety assessment (antibiotic susceptibility, hemolytic, and DNase activities) were also conducted. Among the ALAB strains, Lactiplantibacillus plantarum P2 exhibited excellent probiotic traits and was selected for the preparation of a milk‐cereal‐based beverage (MCBB). The prepared beverage showed good nutritional, sensory, and microbial quality and exhibited 9‐day shelf life under refrigerated conditions. However, survivability of probiotics in the product was found at 6.68 ± 1.24 log 10 CFU/mL up to 15 days which was more than the recommended limit of 1 million CFU/mL. The study confirms the strain's suitability as a potential probiotic starter culture.