The alcohol content of red wine vinegar is small and no more than 2 percent. Wine vinegars, such as white wine vinegar, red wine vinegar and balsamic vinegar, begin with a weak wine, which is then fermented.
With red wine vinegar, most of the alcohol present is used up by bacteria in the fermentation process. After this process takes place, the alcohol remaining will only be trace amounts. For example, a tablespoon of red wine vinegar may only have one drop of alcohol in it. Red wine vinegar is mostly used as a cooking ingredient, but was also used as a mild acid in the past.