Microbiota and phytochemical composition of locally- and industrially-produced vinegar

Purpose: To determine the microbiota and phytochemical compounds present in locally and industrially produced vinegar. Methods: Isolated microbiota from the locally and industrially produced vinegar were identified using next-generation sequencing methods. The phytochemical content was evaluated using standard methods. The FTIR spectroscopic and GC-MS spectrometric analyses were conducted to identify the functional groups and constituents of vinegar samples. Results: Acetobacter species were found in all vinegar samples except Vin D (Bragg raw unfiltered apple cider vinegar), representing the industrially produced vinegar. The presence of Fusobacterium necrophorum and Legionella species showed the need for pasteurization to prevent transmission of infectious organisms. Phytochemical analysis of the samples indicated the presence of flavonoids in all vinegar samples, while FTIR revealed the presence of functional groups such as alcohol, carboxylic acid, alkenes, amines and cyclic alkenes. The GC-MS showed the presence of acetic acid as well as other organic acids, alcohols and ketones in all the samples. Conclusion: The vinegar samples contain acetic acid bacteria and flavonoids, with no substantial variation in phytochemical content of the local and industrial vinegar samples. The identified metabolites may contribute to the nutritional quality of vinegar.