Isolation and Functional Characterisation of Probiotic and Aroma-Active Microbes from Hentak, a Traditional Fermented Condiment of Manipur

This study hypothesizes that microbes isolated from Hentak, a traditional fermented fish paste of Manipur, possess potential probiotic and aroma-producing properties. The dataset includes detailed morphological, microbiological, biochemical, physiological, flavor-genic, and statistical analyses of microbial strains isolated from Hentak.

Key data includes:

• Sample Collection: Hentak samples were collected from various households in Manipur.

• Isolation and Colony Morphology: Microbial strains were isolated on NAM and MRS agar and examined for colony morphology.

• Biochemical and Physiological Tests: Proteolytic, lipolytic, carbohydrate fermentation assays, Gram staining, IMViC, catalase, and oxidase tests were performed.

• Flavor-Inducing Potential: Strains were tested for their capability to induce flavor in curd and beer preparations, assessed through sensory evaluation.

• Probiotic Potential: Strains were assessed for their safety using hemolysis test, NaCl tolerance test, Phenol tolerance, Tolerance to acidic conditions, Antibiotic susceptibility test, In-vitro adhesion to chicken crop epithelial cells test, Auto aggregation test, DNase activity test.

• Flavor Compound Analysis (GC-MS): Gas Chromatography-Mass Spectrometry was performed to identify key volatile flavor compounds in fermented products.

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

• 16S rRNA Identification: Molecular identification confirmed the taxonomy of the most promising strain.

Notable Findings

• Three microbial strains (Hentak/NA/1, Hentak/NA/3 and Hentak/NA/5) exhibited positive proteolytic, lipolytic, and carbohydrate fermentation activity, and were non-pathogenic. These strains were used for the preparation of curd and beer.

• Statistical and sensory analysis (p < 0.05) confirmed a significant relationship between microbial biochemical activity and the production of flavor compounds.

• Sensory evaluation rated Hentak/NA/5 highest for both curd and beer, enhancing aroma, sweetness, and texture.

• GC-MS analysis of Hentak/NA/5-derived curd and beer revealed important flavor compounds such as esters, aldehydes, ketones, and aromatic hydrocarbons—specifically L-Aspartic acid, Pyridine, O-Xylene, Decane, and Benzene—contributing to a sweet and aromatic flavor profile.

• Strain Hentak/NA/5 stood out with superior flavor production and probiotic potential.

• Hentak/NA/5 was identified as Exiguobacterium acetylicum strain FPIH1, which demonstrated non-pathogenicity and superior flavor-enhancing capabilities.

Exiguobacterium acetylicum strain FPIH1 is a promising probiotic candidate and potential starter culture for industrial fermented food production due to its robust probiotic properties and flavor-enhancing ability.