AAB were detected in samples taken at various points in the production line, ranging from the introduction of the semi -processed products to the end of fermentation process. AAB were not detected in the raw materials; they first appeared in the base fermentation after addition of the Koji, Nuruk, and yeast starter cultures. Contamination of the starter cultures is the most likely source of AAB in the main fermentation processes. Growth of AAB can be problematic because they produce acetic acid that can result in negative organoleptic properties such as off-flavor and taste. vinegar-like sourness, bitterness and an acetic acid odor (Bartowsky & Henschke, 2008; Bartowsky, Xia. Gibson. Fleet. & Henschke, 2003) Producers of rice wine need to consider AAB population sizes and prevent over-growth to avoid undesirable effects