Isolation and Characterisation of Flavour producing microbes from Berma, a traditional fermented fish of Tripura

This study hypothesizes that microbes isolated from Berma, a traditional fermented fish product of Tripura, exhibit significant probiotic and flavor-producing potential. The dataset includes detailed morphological, microbiological, biochemical, physiological, flavor-genic and statistical analyses of microbial strains isolated from Berma. The key data comprises:

• Sample Collection: Details of Berma samples collected from various locations in Tripura.

• Isolation and Colony Morphology: Microbial strains were isolated on MRS agar and Nutrient Agar and examined for colony characteristics such as shape, color, and texture.

• Biochemical and Physiological Tests: Various biochemical assays, including catalase test, oxidase test, and IMViC, were performed to characterize microbial strains.

• Flavour-Inducing Potential: Strains were evaluated for their proteolytic, lipolytic, and carbohydrate fermentation abilities, as well as their pathogenicity.

• Probiotic Potential: Evaluation included hemolysis test, NaCl tolerance, phenol tolerance, acid tolerance, antibiotic susceptibility, in-vitro adhesion to chicken crop epithelial cells, auto-aggregation, and DNase activity tests.

• Flavor Compound Analysis (GC-MS): Gas Chromatography-Mass Spectrometry identified key volatile compounds contributing to sensory attributes.

• Statistical and Sensory Evaluation: Sensory scoring for appearance, aroma, flavor, and mouthfeel of curd and beer confirmed the flavor-inducing potential of the strains.

• 16S rRNA Identification: Molecular identification confirmed the taxonomy of selected microbial strains.

Notable Findings:

• Five microbial strains (BER/NA/1 to BER/NA/5) exhibited strong proteolytic, lipolytic, and carbohydrate fermentation abilities.
• Statistical analysis (p < 0.05) confirmed a significant relationship between the biochemical properties of the microbes isolated and their potential to produce flavor compounds.
• Strains BER/NA/1, BER/NA/3 and BER/NA/4 were non-pathogenic in nature. These strains were used for the preparation of curd and beer.
• Sensory evaluation confirmed BER/NA/4 as the best-performing strain, significantly improving aroma, flavor, and texture in curd and beer.
• GC-MS analysis revealed key flavor compounds, including esters (ethyl acetate), aldehydes (butanal), and ketones (cyclohexanol), contributing to desirable sensory attributes.
• BER/NA/4 exhibited excellent probiotic potential, including strong acid and phenol tolerance, NaCl resilience, significant auto-aggregation, and adhesion to epithelial cells, with no DNase activity, while antibiotic susceptibility tests showed sensitivity to major antibiotics.
• Molecular characterization identified BER/NA/4 as Bacillus paralicheniformis strain FPIB1 with notable probiotic and flavor-enhancing potential.
• Bacillus paralicheniformis strain FPIB1 holds promise as a probiotic starter culture for flavor-rich fermented foods.