By-product liquid obtained after distillation of rice spirit contains some suitable ingredients for growth and acetic acid synthesis of acetic acid bacteria. At the same time, unique aroma of this by-product liquid plays an important role in the formation and development of vinegar flavor. Utilization of by-product liquid from rice spirit distillation for production of highly acidic vinegar by mutant strain Komagataeibacter saccharivorans A2 NV120.3 increased value of the waste source, decreased product price and minimized environmental pollution. The kinetic assay of the vinegar fermentation process on medium supplemented by 20% (v/v) by-product liquid from rice spirit production stated that when the fermentation time is 120 hours and total supplemented alcohol of 10% v/v then resultant vinegar product had the concentration of the acetic acid of 10.20% and the fermentation yield was 93.56. Especially, vinegar fermented on medium supplemented by by-product liquid from rice spirit distillation process contained some unique aromatic compounds such as: acetic acid, ethyl acetate, isobutyric acid, benzeneethanol, propanoic acid, 3-hydroxy-2-butanone, 2.4.5-trimethyl-1.3-dioxolane, acetaldehyde diethyl acetal, etc. The resultant vinegar has volatile compounds as determined by GC-MS analysis same as Ajinomoto vinegar. In addition, as evaluted by sensory analysis method, the vinegar has comparable quality with the above Ajinomoto vinegar in term of flavor.
