Identification and multifunctional characteristics of lactic acid bacteria isolated from type I sourdough microbiota using dna marker systems

Within the scope of the study, 350 LAB strains were isolated from 65 Type I sourdough samples and characterized with RAPD markers. Species identification was made by sequencing 16S rRNA regions and they were identified as Companilactobacillus crustorum (n = 135), Levilactobacillus brevis (n = 125), Latilactobacillus curvatus (n = 40), C. paralimentarius (n = 32) and Lactiplantibacillus plantarum (n = 18). 66 LAB strains with different genetic distance were selected and their technological properties were determined with commercial strains. Technological findings were examined by principal component analysis (PCA) and 12 L. brevis and 2 L. plantarum strains, which were found to be competitive or superior to commercial strains and did not carry antibiotic resistance, were selected to determine their probiotic properties. No significant difference was detected between technological properties and different genotypes (P>0.05). L. brevis L62.2 and L. plantarum 7.8 strains (S. cerevisiae M33T1 as yeast strain) were selected to be used in bread experiments, which were determined to be competitive with Lactobacillus rhamnosus GG in terms of probiotic properties by TBA. It was determined that n-hexanal component increased when endogenous strains were used compared to sourdoughs produced using commercial sourdough preparation. No statistically significant difference was detected between the hardness, stickiness and chewiness parameters between the control group bread and the others (P>0.05). Although no significant difference was detected between the general appreciation scores, E3 (S. cerevisiae M33T1-2 + L. brevis L62.2) sample was liked more in terms of shell hardness and color, and E2 (S. cerevisiae M33T1-2 + L. plantarum L7.8 + L. brevis L62.2) sample was liked more in terms of sour odor (P<0.05). The findings show that endogenous strains may give superior results compared to commercial preparations in terms of some volatile components, textural properties and some sensory parameters.