Kefir does have alcohol content, but it is so low (around 0.2% if I remember correctly). In order to minimize the alcohol content in kefir, consume it as soon as you prepare it. The longer kefir waits, the higher its alcohol content. If you let kefir stay for 1 year, its alcohol content increases to 4%, which is still low. An example to compare is beer: Beer has between 4% and 6% alcohol content.