The bacterial component of Kombucha is made up of several different species, nearly often including the acetic acid-producing Komagataeibacter xylinus, which converts alcohols made by yeast into acetic and other acids while reducing the amount of ethanol. Following the first four days of fermentation, the population of bacteria and yeasts known to create acetic acid has been documented to decrease. produces bacterial cellulose and is thought to be in charge of most, if not all, of the "mother's" physical composition. Brewers may have chosen to favour this strain over others over time because it produces firmer, denser, and more robust cultures. During overfermentation, large quantities of acids resembling vinegar are produced. The beverage normally has a pH of around.
