Investigation of physicochemical properties and identification of dominant bacteria in several samples of traditional date vinegar

Discovering new strains with useful industrial and pharmaceutical capabilities and avoiding the import of microbial strains from three economic perspectives, passive defense and conservation of the countrychr('39')s microbial genetic resources are of great importance. The presence and activity of appropriate microbes is an essential factor in the success of fermentation processes. Fermented foods and beverages are among the most important and best natural sources for discovering useful strains. In this study, samples of traditional date vinegar were obtained from Kerman market and their physicochemical (pH, acidity, total soluble solid, total phenolic compounds, and antioxidant activity) and rheological properties (consistency coefficient and flow behavior index) were investigated, also their microbial population were assessed by molecular methods (ARDRA and 16S rRNA gene sequencing) for the presence of acetic acid bacteria. The result of this study was to identify two species of acetic acid bacteria, namely Acetobacter pasteurianus and Komagataeibacter europaeus. In addition, Lactobacillus sp., Paenibacillus sp. and Staphylococcus epidermidis were detected in vinegar samples. On the other hand, vinegar sample were different in terms of microbial load and the type of available microbes. Date cultivar, production method and vinegar age are the possible causes of this variations. Finally, the application of acetic acid bacteria identified in this study as starter culture for fruit vinegar production is suggested. These bacteria were stored with FCC-10971 and FCC-10973 codes in the Food Culture Collection of Shahid Bahonar University of Kerman and can be ordered by other researchers.