Ever since kombucha has exploded onto store shelves as the coolest drink in the Functional Beverages category (according to industry folks, this means that they have a perceived or real health benefit as their primary appeal), people have been searching for the next cool thing in drinks to commercialize. Some companies are already cracking the code, but water kefir is far from new. It lends itself best to home-made, or micro-brewed batches, so I think it’ll be awhile before they get it right. In the meantime, I recommend you search out some kefir grains and try it for yourself!
Water kefir, also known as sugar kefir, fruit kefir, tibicos, ginger beer plant among other names, is a probiotic, fizzy drink that can range from quite sweet to very lemon-y. Water kefir has many variations and is used to ferment drinks in many corners of the world, from Hawaii, to the Phillipines and South and Central America. It has local names, and slightly varied appearance in terms of opacity and strength of the physical grains. The cultures passed around locally have adapted to local fruit sugars, and each carries a different complex of bacteria and yeasts.
Some people prefer it to kombucha for its clean, less yeasty taste. The taste is sometimes compared to sparkling lemonade or cider. Since no tea or herbs are necessarily added, it also does not have that slightly bitter taste that kombucha can have.
The water kefir culture is referred to as kefir grains. Quite unlike the kombucha SCOBY pellicule and also un-related to dairy kefir (which looks more like gelatinous cauliflower florets), the translucent, gelatinous so-called ‘grains’ range in size from tiny gravel-like bits to pieces as big as marbles. They are somewhat fragile, breaking apart when stirred or handled. A matrix of live bacterial cultures, proteins and yeasts, the water kefir grains are actually another form of SCOBY, different from kombucha or jun, but a Symbiotic Culture of Bacteria and Yeast nonetheless.
Where to get water kefir grains?
As with kombucha SCOBIES, if you can track down a community of people who ferment various foods and drinks, you will likely bring up water kefir, and be hot on the tracks of someone who makes it and will share the grains with you. In my experience, since they are somewhat more care-intensive than kombucha, they are a bit trickier to track down. The labs that grow and ship cultures – Cultures for Health as well as GEM cultures – will ship dried, live (not powdered) water kefir cultures to you that you can re-hydrate using their instructions. They should liven back up and start brewing soon, even reproducing so you can share them with your friends.
What to feed water kefir
The medium that water kefir grains prefer is plain sugar, along with some nutrients from fruit.
The most assured method to ferment water kefir is with plain, refined sugar, filtered/clean (but not distilled!) water and optionally adding some pieces of fruit to flavour and increase nutritional value. You can also culture coconut water or fruit juice, but I recommend keeping some kefir grains always in a sugar medium as backup.
This recipe yields a quantity (just 1 liter compared to kombucha which is usually brewed in at least 4 liter batches). Because the fermentation time is short (2-5 days) and the grains need to be fed regularly, it makes sense to make smaller batches more often to keep the grains in regular use.
Note: Unlike kombucha SCOBIES, the water kefir grains do not thrive in a very acidic medium. If you over-brew your grains, they will literally pickle! These somewhat more fragile grains need to be moved to another batch of sweetened water every 2, or maximum 3 days to stay healthy. I had over-brewed a batch once and the grains shrunk almost to the point of disappearing! Needless to say, I had to start over with fresh grains when I was ready to be a better kefir-care-taker.
Fermenting fruit juices and adding syrups
Kefir grains can ferment fruit sugars too, so you can experiment with your excess grains (always keep some in plain sugar-water). Fruit juices that are not too acidic work to produce a fizzy drink. Just put 120-150 ml (4-5 tablespoons) grains into pear, apple, apricot, peach or berry juices. Ferment for 2-3 days and bottle, keeping bottles at room temperature for another 2 days, or until fizzy. For more acidic juices such as passion fruit, guava, citrus, etc., dilute the juice with ½ sugar-water mixture.
Syrups can be added; start with 30 ml (1 tablespoon) of syrup in the secondary (bottled) fermentation. Add maple syrup, molasses, pomegranate molasses or any fruit concentrate syrup or cordial that you love.
Care for your kefir grains
Water kefir takes 2-6 days to ferment, and so is a relatively quick process. The culture is a bit more sensitive than the kombucha culture is. If it is left to over-ferment, the acid that results from the conversion of sugar can actually harm and then kill the culture! Water kefir grains prefer to be fed quite often which is why when I brew mine, I make 1 liter (1 quart) at a time, keeping a rotating jar of water kefir on the counter, mixing up a new batch every few days as I bottle the last batch. Once you find how much water kefir your household consumes per week, you can find your rhythm. Halve or double the batch to keep your culture fed regularly.
What about remaining sugar and alcohol in water kefir?
The fermented water kefir has about 20% the amount of sugar of the original and almost all of it has been converted from sucrose to fructose. As glucose is consumed by the grains it is turned into beneficial organic acids and Co2 (fizz) and very small amounts of alcohol — usually about 0.5-0.75%, but up to about 3% under the right conditions. 
