Second Fermentation: How to flavour your kombucha

4min read

By Freya Twigden, Head Fermentalist @ Fix8

  • Second fermentation allows you to add fizz and additional flavour to your kombucha. 
  • There are some basic rules but it is a great opportunity to be creative. 
  • Be aware of the amount of sugar you are adding some of it might be hidden. 
  • Don't forget to keep back at least 10% from your first ferment for your next brew.

So, your kombucha is ready.

Firstly, give yourself a pat on the back for successfully brewing kombucha! A new skill you can add to your CV.

Next, you might want to add some fizz and flavour to your kombucha to enhance the kombucha character, add medicinal benefits and sophistication to your craft brew. 

So what is second fermentation?
In the first fermentation, sweet tea is transformed into kombucha. In a second fermentation, we add flavour and fizz to your kombucha brew. And a personal creative touch, if you like.

Second fermenting kombucha is akin to ‘bottle conditioning’ in the beer world.

What can I use in a second ferment? 

You can use whatever you like to flavour your kombucha with! There are no rules. Once the SCOBY / starter liquid has been removed and set aside for your next batch, you can add anything from dried or fresh fruits, spices, herbs, barks, flowers - it’s a chance to be creative!

How to flavour:

  1. Pour ready brewed kombucha into a glass flip-top bottle.
  2. Keep 10% of the starter liquid and SCOBY in the brewing vessel, this will be used for your next batch.
  3. In your flip-top bottle, add whatever flavourings you choose! 
  4. Seal the bottle so that it is airtight, and leave for a further 3-6 days on the counter, at room temperature to carbonate.
    (Alternatively, you can flavour the ready kombucha and pop it straight in the fridge to drink if you do not want to add fizz to the bottle.)
  5. Burp your kombucha every few days to release some gas. A build-up of gas can potentially lead to a ‘kombucha explosion’, so make sure you are in tune with how fizzy your kombucha is getting by checking it daily. 
  6. Once at desired fizz and flavour, pop in the fridge, strain and enjoy chilled.

Guide to quantities:
I usually add about 5-10% flavouring. For example, if I was bottling a 1L brew then I would add approximately 100ml fruit juice or 50g fresh fruit. There is not ‘precise’ guide here.

If I am using something stronger, like ginger root, I'd use 2-3% (20ml for a 1L bottle of kombucha). If you are adding in spices, remember, a little goes a long way. I add about ¼ teaspoon per litre of spice (for example, I recently added ¼ tsp chai spice mix to 1L freshly brewed kombucha).

Again, these are just rough ideas, you might prefer more or less flavour in your kombucha so I encourage you to experiment with quantities here!

Some flavour combinations I am loving recently…

Rhubarb & Vanilla
Grapefruit & Juniper
Cardamom & Honey
Chai Spiced Kombucha

Mostly, have fun with adding flavouring, be creative... and don’t forget to burp your booch!


A DEEPER dive + what to consider with your second fermentation:

For a more deeper dive into the second fermentation of kombucha, here are a few thoughts to consider when second fermenting your freshly brewed booch:

  • TEA:
    Think about the tea you used. What flavour kombucha has it produced and which flavours pair nicely with the tea? For example, white tea might lend itself to more delicate flavours like apricots, peach, rose. Black tea kombucha often produces a bolder flavour, therefore is a good carrier to stronger flavours - like ginger root or spicy chilli’s.

    Think about the temperature. Hotter climates or times of the year, your kombucha brew (and second fermentation) will move a bit faster. So be mindful of this, burp your kombucha more regularly. Equally, if it’s winter, perhaps you might double the length of time you second ferment for as in a cooler temperature, it will be slower.

    Think about what's in season. Rhubarb might be a nice option for now, with the arrival of spring. Coming into summer, I love using fresh British raspberries and strawberries in my homebrew kombucha. October is a nice time for a seasonal apple or pumpkin spice kombucha, you can be creative!

    Think about sugar. If you are adding high sugar fruits like mangos, pineapple or grapefruit, you are adding more sugar to the kombucha. This will feed the yeast in your second fermentation and make them excited, resulting in a more carbonated beverage. So be careful, if adding flavour to your kombucha with a high sugar content, you are more likely to get an active, and fizzy kombucha (so burp it more regularly!).


It’s fun to think about what you already have in your cupboards, fruit bowl or on the spice rack. There’s no need to go and buy lots of ‘exotic’ ingredients, being creative with what you have is one of my favourite challenges. 

I often go straight to my spice cupboard and see what’s looking interesting. I recently made a delicious white tea, honey and cardamom kombucha - simply because cardamom was the first spice I saw when I opened the cupboard to choose my flavour! 


Freya Twigden is the Founder and Head Fermentalist at Fix8.  When she isn't brewing Kombucha she spends her time practising yoga, riding her bike and finding out what you can (and can't) ferment.

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