Acetic acid bacteria are usually airborne and are abundant in nature. They are present in environments where ethanol is being formed as a result of fermentation of sugars by yeasts, such as with flower nectar, ripening fruit, and beer making. In these liquids they create a surface film. They need oxygen to survive, so they live on the surface where they can access it.
The word "bacteria" can invoke horror in some people, but this variety of bacteria are among many of the good guys.
Sometimes the mother develops in stored vinegar. It can easily be removed by pouring the vinegar through a coffee filter if you wish, and can be saved in the fridge and a pinch added to jump start a new batch of vinegar.
If you choose, you can just mix the mother right into the vinegar and use the whole works. The mother is the most nutritious part of the apple cider vinegar, after all.
Always opt for raw, organic apple cider vinegar. Natural enzymes, minerals, and nutrients are destroyed in the distilling process. There is no nutritional value in vinegar that is clear and has no "mother". Natural, raw vinegar will be pungent with a rich, brownish color and a visible "mother." You can learn how to make your own homemade apple cider vinegar here.
Credit For Content:
US National Library Of Medicine - National Institutes For Health