I have become obsessed with fermented foods. Sourdough bread, sauerkraut, yoghurt, milk kefir and water kefir have all become part of my daily diet. If I were to buy these fermented foods from a health food store, I’d be spending a small fortune on my habit. Thankfully, fermented foods are easy to make at home.

My current favourite ferment is water kefir.

Water kefir is a naturally fizzy fermented drink laden with probiotics.

It is bubbly and refreshing like soft drink, but without the artificial ingredients and with far less sugar. The beneficial bacteria and yeast are an added bonus. 

You can buy water kefir from many heath food and organic stores. Here in Newcastle we’re fortunate to have it made locally by a small family business. Imbibe Water Kefir is delicious, but at $12.95 for a bottle it’s a drink I reserve for special occasions.

You can make your own water kefir at home for only a few cents per litre.

You’ll need some water kefir grains.

Despite their name, water kefir grains aren’t actually ‘grains’. They are small translucent bundles of yeast and bacteria living symbiotically.

You can buy water kefir grains online, but I think cultures are best shared.

Find someone who makes water kefir. Perhaps a friend of a friend. And ask for some grains and culturing tips.

I like the idea of cultures being used to culture community.

For me, sharing my excess grains is part of the fun of making kefir. A friend gifted me some grains and I have since passed on grains to others. Kefir grains have been shared like this across the globe for hundreds of years.

There are many stories about the origin of water kefir. One story suggests it originated in Mexico, where water kefir grains were collected from a prickly pear cactus. Another, and my favourite, suggests it originated in Tibet where monks gifted some grains to Mother Theresa to improve the health of India’s poor. There was a condition on the gift, that it must never be sold. It should to be shared for free instead.

Whatever the origin of water kefir, I love that my bottles of beneficial yeast and bacteria are decedents of microorganisms that have been drunk and shared for hundreds of years.

How to make water kefir 

Step 1: Make a sugar solution

To a large two litre glass jar add: 

1/2 cup of raw sugar
1/4 teaspoon of coarsely crushed sterilised egg shells
1/4 teaspoon of bicarb soda (baking soda)
1 teaspoon of molasses (optional)

Water kefir needs a solution rich in minerals to thrive. The egg shells, bicarb soda and molasses provide the minerals the kefir grains need to thrive. Molasses does have a distinctive taste that not everyone in my household likes, so I don't always include it. In the picture above, the middle jar contains molasses. 

To make sterilised egg shells, I wash the shells as I use them and collect them in a bowl. I then place the bowl in the oven at 110 degrees celsius for 10+ minutes. Cool, crush, and store in a jar. 

Add one cup of boiling water to the jar. Stir until sugar is dissolved. Add 7 cups of water.

The type of water you use will influence the health of your kefir. Spring water is ideal, rainwater is good, and tap water is fine, as long as you evaporate off the chlorine first. Chlorine can damage the kefir grains. The chlorine can be evaporated off by letting the water sit overnight before using. 

Step 2: First ferment 

Add one cup of kefir grains to the jar of sugar solution. 

Put a lid on the jar or cover with a cloth. Leave to ferment at room temperature for 24-48 hours. 

The longer you ferment, the lower the sugar content of your final drink, thanks to the appetite of the yeast and bacteria.

Be aware, there's apparently a risk of jars exploding under the pressure of carbonation (a product of the fermentation process). If you are new to making water kefir and are not sure how active your grains will be, I suggest covering your jar with a cloth rather than a tightly closed lid. I like bubbles, so screw my lids on tight. 

Step 3. Strain grains from sugar solution. 

After one to two days, strain grains from the sugar solution. 

If your kefir grains are happy, they will multiply each batch – leaving you with more than enough to share. I've also been feeding excess grains to our dogs and chickens. 

Note: Once you get to your second batch you will do this step first so that you have grains for the next batch. i.e. when you are ready to make your second batch you will do step 3 (strain grains) first, then step 1 (make sugar solution), then step 2 (first ferment), then step 4 (second ferment). 

Step 4. Second ferment. 

The second ferment is where the fizz is enhanced and extra flavours are added.

Place your strained water kefir into sealable bottles, add fruit or juice to flavour, seal lid and turn bottle a few times to mix. Leave to ferment at room temperature for another day.

Almost any fruit or fruit juice can be used to flavour water kefir.

Here's a few of my favourite flavours so far. To a one litre bottle I add the following: 

• Ginger and lime: a teaspoon of ground ginger and a couple of slices of lime
• Lemon: the juice of 1/2 a lemon
• Peach: the flesh of one peach chopped
• Mango: I use a jar rather than a bottle and add an entire mango seed still covered in flesh
• Apple and cinnamon (shown above): 1/4 apple chopped + 1/2 teaspoon ground cinnamon. 

Experiment with your favourite seasonal fruits. I'm looking forward to grape and bluberry season. 

Be careful when opening the bottle after the second ferment as it may be supper fizzy and overflow. There's also apparently a risk of bottles exploding under the pressure of carbonation. When I'm second fermenting with a super sweet fruit like mango, I leave more space at the top of the bottles and also open the lid every now and then to release pressure. One day I'd like to collect some swing-top style brewing bottles with rubber seals as they expand under pressure. 

Place in the fridge to chill before serving.

Repeat. 

Water kefir grains need to be fed a fresh sugar solution every 48 hours or they will starve. If you want a break you can store the grains in a sugar solution in the fridge. Replace the sugar solution once a week. For longer-term storage you can dehydrate the grains and store in the fridge for six months.