Strawberry water kefir

Strawberries are the easiest fruit to start with when you first add flavour to water kefir. They give up their colour within hours, their sugar feeds the second fermentation, and you end up with a pale pink drink that is sharp, lightly sweet and properly fizzy. Children who turn up their noses at plain kefir tend to ask for a second glass of this one. Adults drink it from a wine glass with plenty of ice.

Which strawberries work best

Ripeness matters far more than size. In June and July, when British strawberries are at their best, the small, dark red berries sold by the punnet have much more flavour than the big pale ones on the shelves in winter. A few soft strawberries that are past their best for the table are perfect here: they give plenty of juice and sugar, and nobody sees them once they have done their work.

Out of season, frozen strawberries do the job well. Let them thaw in a bowl and tip the juice into the bottle along with the fruit. Freezing has already broken the cells, so the colour comes out faster and turns deeper, and the flavour leans a little towards strawberry jam. On a wet February evening that is no bad thing.

It all starts with the first fermentation

How the finished drink tastes depends largely on the batch you start with. Taste before you strain: the kefir should still be slightly sweet and already clearly tart. If it is still very sweet, give it a few more hours on the worktop. With 60 g of grains you can make 2 litres at a time and flavour two bottles, one with strawberries and one with something else.

The full basic method is in How to make water kefir, and everything about the closed bottle stage is in the guide to the second fermentation. If your tap water smells of the swimming pool, read water and sugar for water kefir before your next batch.

Variations

• Strawberry and mint: add four fresh mint leaves to the bottle. Cool and very summery.
• Strawberry and basil: two basil leaves in the bottle and a twist of black pepper in the glass. It sounds odd and tastes surprisingly grown-up.
• Strawberry and rhubarb: 100 g strawberries with 2 tablespoons of the syrup from the rhubarb water kefir. Both are around in May and June.
• Strawberry and elderflower: one or two flower heads in the bottle, as in the elderflower water kefir. Fragrant and fruity at once.
• Strawberry and lemon: the juice of half a lemon makes it drier and sharper.

Serving and storing

Pour it cold, through a tea strainer, over a few ice cubes, with a slice of strawberry on the rim. For a summer jug, dress it like a classic summer fruit cup: sliced strawberries, a few ribbons of cucumber and a handful of fresh mint. It makes a good alcohol-free drink for a birthday, a christening or a long evening in the garden, if the weather holds. If you would rather freeze it, the water kefir ice lollies use the same flavours.

Keep an opened bottle in the fridge and drink it within a few days. The cold slows the fermentation down without stopping it, so the drink gets slowly drier and sharper. The strained strawberries are soft and tangy: stir them through yoghurt or spoon them over strained kefir cheese.

Frequently asked questions

No grains in the house yet? With our live water kefir grains you can start a new batch every day. All the recipes and guides are on the water kefir page.