I know your post is very old, but just in case you see this post, yes, you can brew kefir drinks with non milk media but the grains will stop propagating (this is if you have milk kefir grains). If you have sugary kefir grains (also called water kefir grains), you can brew non milk drinks and the grains will keep growing.
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Re: Is anyone familiar with kefir grains and could they be used in soy,rice or almond milk?
