A blog I stumbled upon, and now follow, is Frugal by Choice, Cheap by Necessity. Sarah, the blog author, wrote about making water kefir "soda" and that intrigued me. It took me a while to gather everything up and get the kefir going strong, but I've finally gotten it working.
(I use a 1/2 gallon mason jar)
4 Cups Chlorine-Free Water
(I use Glacier filtered water that is left out for 24 hours)
4 drops Trace minerals (if using filtered water)
(I prefer to use evaporated cane juice)
1/3 Cup kefir grains
Put all the ingredients, save the grains, in the jar and stir until the sugar is dissolved. Some people heat up the water to make it easier to dissolve the sugar, but room temperature works well for me, but you want the water to be room temp before adding in the grains. Cover the container with something that lets air in, but keep bugs out. I either use a seed sprouting lid or a jelly bag.
In the next day or two the kefir grains will eat the sugar and turn it into another form of sugar, fructose I think. Filter the grains out to start another batch of kefir water.
Now you should have about four cups of water kefir. You can drink it as-is, but I'm not aiming for some sweet water, but a base for some soda replacement. At this point I add 1 cup of 100% fruit juice. Sarah recommends sticking with the purple juices, which is advice I've stuck with. I like to use a blend of juice. Once that is mixed I put it into some flip top bottles and let it sit our for about 48 hours. At first I was needing to keep it out for three days to get any carbonation.
When your water kefir "soda" is done, simply place it in the fridge and drink it when it is cold. Take care to use the soda in a reasonable amount of time because it will continue to ferment, albeit a slower rate. If you leave the bottle out too long they will continue to pressurize as the water kefir converts the sugars in the juice to small amounts of alcohol and a decent amount of carbonation. Taking the advice of several people, place a towel over the bottle before you open it....just in case.
The obviously answer is to simply label the bottles. The thing is for me, just exactly how? I thought about using tags, paper labels, even china markers. The thing is I don't want to be having to clean labels off of the bottles or fiddle with tags. This morning it came to me....a simple ring that would slip over the bottle top would work. I could make some rings, but in the end I just took a marker to some mason jar rings that easily slip on and off the bottles. Now I know when each bottle was put away.