How to Make Water Kefir

How to make Water Kefir

DAY 1: You will need…..

  • Sachet of water kefir grains (30g)
  • 50g sugar (see below for which type)
  • 1 litre of water ( 50 ml hot ; 950 cold)
  • a 1 litre plastic bottle or a 1l glass kilner jar WITHOUT gasket or a glass jar with lid that can be left on but loosened.
  • a tablespoon of raisins and a thin wedge of lemon (don’t squeeze) – this provides some extra minerals to get things going, not always necessary.


  1. Ensure your equipment, hands and work surface are clean and free from possible contamination by raw animal, pet or grubby-vegetable matter. Work smartly to minimise the chance of uninvited air borne microbes joining the party.
  2. Dissolve the sugar in the hot water (this is purely to speed things up, you can just stir a lot if you prefer). If you are using a plastic bottle, use a jug for this stage or you will melt the bottle J. Then add the cold water. This will give you a 5% sugar solution that is the ideal temperature for your kefir grains. If you have used too much hot water, wait until it has cooled to room temperature before adding the grains or you will kill the microbes.
  3. Add your room temperature sugar solution to the bottle or jar, then put in the kefir grains. Some may float or they may all gravitate towards the bottom. Then add the lemon and/or raisins. This is some extra hep to get your kefir grains started.
  4. Leave your ferment on the worktop for 24 hours (the grains may need little longer after transit). If you move the jar or bottle slightly you should see bubbles of carbon dioxide (CO2) forming. Taste a little (either use a spoon or strain a little into a cup through a sieve or you might end up with a mouthful of grains – not that they’ll do you any harm). If it tastes too sweet, leave for another few hours. When it tastes to your liking with a good amount of fizz and just a hint of sweetness you are ready to strain the water kefir. You can leave your ferment for up to 72 hours but after this, the grains will begin to get rather hungry.

DAY 2: you will need…..

  • a sieve
  • a jug
  • a funnel if transferring to bottles.
  • a storage container for your kefir water – bottles or jars, glass or plastic, just not 250ml kilner gasketed bottles (see below).
  1. Set up your sieve over a jug if you want to transfer into several smaller bottles, or you can use a sieve and funnel to transfer directly into a single larger bottle or jar. Any kind of set up that doesn’t make too much mess really!
  2. Strain your ferment through the sieve. Remove the raisins and lemon wedge ( bit fiddly this). The grains can be set aside and covered with some clingfilm while you are dealing with the next stage – they will be fine.
  3. At this stage, the water kefir is perfectly drinkable as it is, though its fizziness can best be appreciated after bottling and refrigerating, whereupon the fermentation will continue at a slower rate and a little more CO2 will be produced, and a very small amount of alcohol. You can keep it in one large bottle, or in several smaller ones. Many folk use it to dilute elderflower or other cordials ( this is delicious and a good way of getting probiotics past cynics and dissenters – my teenage daughter for example). At this stage it is fine to use well-sealed bottles, and you will get a satisfying hiss when you open the bottle but please see note below about suitable vessels for second fermentation
  4. You can also “second ferment” it. This means adding some flavour to the water kefir and reducing some of the sugar content from the added cordial or fruit or fuit juice by leaving it to steep for a day or two before serving. Simply transfer your strained water kefir into a bottle ( or several smaller ones) with some fresh fruit juice (10- 20% volume) or pieces of real fruit or ginger or herbs ( rosemary and mint both work well). I tend to do this for 24 hours at room temperature before putting in the fridge. Strain before serving.
  5. Start again! – transfer those kefir grains into fresh 5% sucrose solution or coconut water and off you go. There’s no need to wash them.

See more about water kefir.