If you've been out for a walk recently, you've probably noticed the hedgerows bursting with juicy blackberries. They're one of the UK's best seasonal treats, and this year they're tasting especially sweet.
At Fizzy Buoys, blackberry is one of the flavours we like to brew this time of year. It creates a deep ruby-coloured kefir, sweet and naturally fizzy.
Why blackberries work so well...
Blackberries are naturally rich in flavour, making them ideal for flavouring water kefir during the second fermentation. As the kefir cultures consume the remaining sugars, they create natural carbonation while extracting all those wonderful berry aromas.
The result? A refreshing, lightly sparkling drink that's perfect served ice cold on a warm summer's day.
Our favourite method: homemade blackberry cordial
At Fizzy Buoys, we make a simple blackberry cordial which we add to our second fermentation. This gives us a consistent flavour throughout every batch while keeping sediment to a minimum.
Simple blackberry cordial
Ingredients
- 250g fresh blackberries
- 100ml water
- 75-100g cane sugar (adjust to taste)
- Juice of half a lemon
Method
- Add all ingredients to a saucepan.
- Simmer gently for 10-15 minutes until the berries soften.
- Mash the fruit with a spoon.
- Strain through a fine sieve or muslin cloth.
- Allow the cordial to cool before using.
Add around 20-40ml of cordial per 500ml bottle of finished first-fermented water kefir before sealing for the second fermentation. Leave at room temperature for 1-2 days before refrigerating.
Can you use whole blackberries?
Absolutely.
Fresh whole blackberries also work brilliantly in the second fermentation. Simply add a small handful (around 6-10 berries) to each bottle before sealing.
As the berries infuse, they'll release their juice naturally into the kefir, creating a slightly lighter, fresher flavour than cordial.
A few tips:
- Gently crush a few of the berries to help release their juice.
- Leave enough headspace in the bottle, as fruit can increase carbonation.
- Strain before drinking if you prefer a smoother finish.
- Refrigerate once your desired level of fizz has developed.
Fresh is best
For the best flavour, use freshly picked, ripe blackberries. Avoid any mouldy or damaged fruit, and always wash foraged berries well before using them.
If you're lucky enough to have a freezer full from previous seasons, frozen blackberries work wonderfully too.
Start brewing
Blackberry season doesn't last long, making now the perfect time to experiment with seasonal flavours.
Whether you choose our cordial method or simply pop whole berries into your bottles, blackberry water kefir is one of the easiest and most rewarding recipes to make at home.
If you're new to brewing, our Water Kefir Starter Kits contain everything you need to get started. Once your grains are active, the possibilities are endless—and blackberry should definitely be one of the first flavours you try.
Happy brewing!
