Seasonal water kefir

To keep my gut nourished with good bacteria, I try to consume something fermented each day. Usually I tend towards sauerkraut, kimchi and pickles, all of which I make at home. I’m still working on a coconut yoghurt that’s better than, or at least as good as, the stuff I can get from my local organic shop, but the same place also sells a de-li-ci-ous water kefir, which is basically like a probiotic soda. My boyfriend and I call it ‘the most refreshing drink in the world’. Lemon and fig flavour, it’s sour, fizzy and oh-so thirst-quenching.

I figured I’d give homemade water kefir a go for a few reasons: I can define the flavour by what fruit’s in season, it’s cheaper than buying the store-bought stuff, and it saves on packaging.

The process involves a two-part fermentation. Technically you can drink the kefir after the first stage, but the second fermentation is where things get tasty, as you add in seasonal fruits for flavour. The image shows a mixture of strawberries and red currants*, but I’ve tried everything from apples and pears to mangoes and oranges. Ginger is a great addition too.

I haven’t (yet) managed to get it as fizzy as the store-bought stuff but, once chilled, it’s still goddamn refreshing. And before you worry about the sugar involved in making it, there’s only residual sugar left in the resulting drink as the rest is gobbled up in the fermentation process.

When cared for properly, the grains can be used indefinitely and will multiply. Mine breed like crazy and I’ve already given batches to a few friends along the way. I also keep a jar of extras in the fridge, which I add into smoothies (around a tablespoon per smoothie).

*Full disclosure: the strawberry-and-red currant combo makes for a pretty picture but wasn’t my favourite. Too much sweetness from the strawberries, not enough sourness from the currants. My instinct tells me if you’re using thick-skinned fruits, mash or muddle them a little instead of adding them whole. I’ll give it a try sometime to find out.

Seasonal water kefir

Equipment needed
  • 1 x large air-tight mason jar (I use one that's around 2.5 litres)
  • A plastic sieve (or do what I do and line a metal sieve with cheesecloth when straining the grains, which don't deal well with metal)
Ingredients for initial fermentation 
  • 1/2 cup x water kefir grains
  • 1/2 cup x organic cane sugar
  • 2 x organic, sulphite-free dried figs, torn in half
  • 2 x lemon quarters, peeled
Ingredients for second fermentation 
  • 1 1/2 cups x chopped fresh seasonal fruit
  • Optional extras: fresh ginger, whole spices like cardamom or clove, fresh herbs


Fill the mason jar up with 2 litres of water and leave, unsealed, overnight. This helps chlorine from tap water to evaporate. You can also use natural spring water instead to start making the kefir immediately.

The next day, add 1/2 cup cane sugar to the jar and stir with a wooden spoon (remember: kefir grains don't like metal) until dissolved. Add 1/2 cup kefir grains to the jar, as well as the 2 halved figs and 2 quarters of lemon.

Seal the jar, then leave on the kitchen counter away from direct sunlight for 2-3 days, the former for warmer months and the latter during winter. I've read that kefir grains like an anaerobic environment (they don't need oxygen to survive), hence the air-tight container. If you want to reduce the (already small) amount of alcohol present in finished water kefir, however, you can use a cheesecloth over the lid instead.

After the fermentation time, use your plastic sieve or a metal one lined with cheesecloth to strain the mixture from the jar into a bowl. Set the grains aside.

Give your mason jar a rinse, then pour the strained liquid back in. Add the fruit and seal. Keep on the kitchen bench for another 24 hours. After that time, the fruit should have risen to the surface and the liquid should have a light fizz. Re-strain to remove the fruit, then store the water kefir in the fridge. A friend tells me that after the second fermentation, she transfers the water kefir solution to a large air-tight bottle – something you might get if you buy beer from the tap at your local hip craft beer store. After leaving this bottle on the kitchen counter for another day or so, the water kefir gets nice and fizzy apparently. Just make sure you 'burp' the bottle once a day if you're leaving it for longer, as bottles like this have been known to explode . . .

To keep your grains healthy, store in a jar with a mixture of water and sugar. I use around one tablespoon per time. If you had leftover mixture from the first fermentation you can also add that in. The grains are happiest when making water kefir though, so as soon as I'm running low on one batch I get a new one rolling.