While we cannot guarantee the safety of your home-fermented water kefir, it is quite safe to make at home due to the very low pH level. The low pH level of water kefir makes it difficult for unfriendly organisms to survive in it. We feel that raw water kefir is best because its raw state is what makes it so healthy to drink. The living bacteria and healthy acids and enzymes that would be destroyed upon pasteurization. Very few commercial breweries pasteurize their water kefir, so your home fermentation setup is no different!