Your comprehensive guide to kombucha carbonation and flavouring. You will find practical, helpful and super flexible tips for kombucha’s second fermentation. Use these tips to create the kind of flavour and carbonation you desire.
In addition to tips on how to make fizzy and flavoured kombucha, I will share my favourite flavour combinations. I have included a base recipe and instructions on kombucha’s 2nd fermentation at the end of this article.



Second Fermentation for Kombucha Carbonation
Kombucha carbonation is created during kombucha’s 2nd fermentation process by infusing kombucha with additional ingredients and let it continue to ferment in a tightly sealed bottle. The microbes continue to feed on sugar and create carbon-dioxide. The carbon-dioxide is trapped in the bottle, therefore creating that fizz when the bottle is opened.
If you only want flavoured kombucha but not the fizz, then you don’t need to 2nd ferment your kombucha. Simply bottle the flavouring ingredients with the kombucha from your first fermentation, and move the bottle into the fridge. You can pretty much re-use any glass bottle. The bottle doesn’t need to be able to hold the pressure.
If you like the original kombucha flavour, and only looking to add some fizz, you still need to 2nd ferment your kombucha. You don’t need to add any infusing ingredients, but you may still need to add some sugar or alternative sweetener, if your kombucha is already fairly tart. The additional sugar is to feed the yeasts and create the carbonation during the 2nd fermentation.
And of course if you want both flavoured and fizzy kombucha, you will need to 2nd ferment your kombucha. The flavour infusion and carbonation are achieved in the same process called the 2nd fermentation.
Before you can begin kombucha 2nd fermentation, you will have to complete kombucha’s 1st fermentation first. You can find everything you need to know about kombucha’s 1st fermentation in 11 important things to know for a successful kombucha brew.
Kombucha Flavouring Tips
Infuse Kombucha with Cut Fruits
Use small pieces of fruits such as fresh or frozen berries, diced apples and pears, cherries and cantaloupes, all will work well. Think fruits that are firm. The fruits used for infusion will get mushy, as they are digested by the microbes in the kombucha. I personally do not enjoy the texture of mushy fruits in a fermented drink. Therefore, I never use fruit puree in kombucha’s second fermentation.
Use Sweet Fruits
Keep in mind your kombucha is already acidic. It will become more acidic after the second fermentation. Adding sweet fruits will balance the sour kombucha flavour. When you use acidic fruits, such as lemon and lime, you may want to add a sweetener at the same time.
Infuse Kombucha with Vegetables, Herbs and Spices
Small slices of ginger really work well, as well as herbs such as basil, mint, lavender and lemongrass. For even more health benefits, use health-promoting foods like goji berries, turmeric, Acai berry powder or spirulina (my exclusive discount code YANG10 will give you 10% off at checkout, when you shop at Perfect Supplements). Try spices like cardamon, cloves and cinnamon. You can create more complex flavours by adding a few drops of pure vanilla or almond extract.
Add More Sweetness if Needed
You may need to add more sweetener, if you are infusing your kombucha with ingredients that don’t contain much sugar. If you don’t like the idea of adding cane sugar in the 2nd fermentation of kombucha, you can use alternative sweetener such as honey, maple syrup, or molasses. Remember a lot of the sugar will be consumed by the microbes in the kombucha instead of going into our bodies.
Create Your Own Flavour Combination
Think about your favourite flavour combination for ice-cream or cocktail to get ideas for your kombucha flavour. What other people like will not be what you like.
More Ideas
My favourite kombucha flavour combinations for second fermentation are:
- pomegranate flavoured kombucha from 3 part kombucha and 1 part pomegranate juice;
- kombucha infused with a mix of strawberries, raspberries, blueberries and blackberries;
- kombucha infused with ginger and pear with a touch of honey for sweetness.
I have heard great things about the Big Book of Kombucha, for even more ideas on kombucha flavours.


Kombucha Carbonation Tips
Use a Good Quality Bottle
You will want to use a high quality bottle that can seal tightly and hold pressure inside, so that the kombucha carbonation you created will not escape the bottle. The best bottle for fizzy kombucha is a flip-top bottle designed for carbonated drinks. The round-shaped flip-top bottles are stronger than the square shaped ones in resisting pressure, therefore less chance for cracking and explosion.
Use Ingredients Containing Sugar to Create Carbonation
For example, bottle your kombucha with sweet fruits, sweet juice, honey, maple syrup, organic sugar etc. for 2nd fermentation. The higher the sugar content of your additional ingredients, the more your are feeding the yeast, the more carbonation you will create.
Ginger Can Make Your Kombucha More Fizzy
Adding pieces of ginger not only create extra flavour, it helps to create more kombucha carbonation as well.
Leave Your Bottled Kombucha to Ferment for Additional Time
Once you transfer your kombucha with the extra ingredients into a tightly sealed bottle, you will want to let it ferment in room temperature for a few more days, before moving to cold storage. The time period for 2nd fermentation can vary depending on the temperature and how active the yeasts are in your kombucha. I talked about how various factors affect yeast activities in your kombucha in my previous article 11 important things to know for a successful kombucha brew. The 2nd fermentation will typically take 3-7 days. The warmer the temperature, the faster the fermentation, therefore the shorter your 2nd fermentation should be.
Check Your Kombucha 2nd Fermentation
Before you are experienced enough to know how long it takes to create the level of kombucha carbonation you desire, you can check along the way. To determine if the kombucha is fizzy enough for you, you can quickly open the bottle and close back. Or you can ferment in a soft plastic bottle along side your glass bottle. When the plastic bottle turned hard, you know it is filled up by carbon-dioxide and your kombucha will be fizzy. Remember how many days it takes, and you can use the same day count as a rough guideline for future batches. Note that the exact length of time will still vary, due to so many factors.
Beware of Explosion
If you leave the kombucha out too long for the 2nd fermentation, the bottle may explode, especially in the summer time. You need to move your finished 2nd fermented kombucha into cold storage before too much air pressure is built up inside the bottle.
Related: More Fermentation Recipes You Will Love
- Honey Fermented Garlic: A Natural Remedy for Cold and Flu
- Pineapple-Turmeric-Ginger Probiotic Sauerkraut
- Wild Fermented Salsa
- Fermented Pickles /w Green Tea and Dill Flowers
- Raspberry Kefir Cream Cheese Spread
- Kefir Fermented Honey Thyme Sourdough Cornbread
- Injera (Fermented Ethiopian Teff Flatbread)
- Fermented Cashew Cheese (Vegan, Probiotic)
- Overnight Banana Spelt Pancakes: Fermented for Better Nutrition and Digestion


Kombucha 2nd Fermentation
Ingredients
- 3-4 cups mature acidic kombucha
- 1-0 cup sweet fruit juice
- 1/4 cup small pieces of fruits such as berries, apple, pear, cherry, canteloupe
- a few slices of ginger
- a pinch of herbs and spices
- 1 tsp sugar, maple syrup, or honey
Instructions
- Filter your mature acidic kombucha through a coffee filter. This is to remove dead yeast strands in the kombucha from the 1st fermentation. Note that more dead yeast will appear at the end of the 2nd fermentation again. However, filtering the dead yeast now will reduce the amount in the final product.
- Fill your flip-top bottle with the filtered kombucha. If you are not planning to add fruit juice later, you can add more kombucha to fill the capacity of the bottle.
- Use any flavour combination from the ingredient list above. You don't need to use all of the juice, fruits, ginger, herbs, spices and sweetener. Choose a combination and the amount that suits your taste. Add your chosen ingredients to the kombucha bottle, make sure to leave at least an inch of air space on top.
- Close the bottle tightly. Let it ferment until it reaches the level of kombucha carbonation you desire. Typically 3-7 days in room temperature between 21º and 29ºC. But could be less or more. See the "kombucha carbonation tips" section for details.
- Move to cold storage when the 2nd fermentation is done. Your fizzy flavoured kombucha will last in cold storage forever!
Nutrition


can i store the second fermentation in an airtight Ball jar?
Hi Yang,
nice blog ! ☺️ I have one question, once I made a flavored kombucha ( with fresh fruit), after the 2nd fermentation, I move it to the fridge, how long can it last in the fridge? I had read on 1 website mentioning that it has be be drink in 2 or 3 days.. .?
Hi Est, thank you for visiting the blog! Once you transfer the kombucha into the fridge, it will last a really long time. It doesn’t expire, and you will most likely consume it within a few months anyways. Hope this helps!
Thank you so much for the info Yang! Sorry, another question, Do I have to strain the fruit pieces or I can leave it inside?
Just leave the fruit pieces inside the bottle. If you open the bottle to strain the fruit pieces, you will lose the carbonation.
Would you advise adding whole pomegranate seeds? or crushing the seeds before adding?
I think both would be fine! Whole pomegranate seeds will look nice but won’t release much flavour. If your goal is to add pomegranate flavour, then it’s better to crush the seeds in order to extract the juice.
Hello! I really liked your article. I was wondering if I can use empty tea bag (from david’s tea) to put lavender buds in it. Id rather be able to remove the bag directly than having to strain my second fermentation bottles. Do you think it would upset the yeast or it would work okay?
Thank you!
Kombu mom <3
Great post.
I have a question, if you were to do second fermentation in a syrup type bottle for 2 days (tested time) would it be ok to refrigerate straight from that to then sell at the local market? Without breaking the seals?
Thank you.
Thank you Olivia! Can you describe what you mean by a syrup type bottle? I am not familiar with it. I use a flip-top bottle in order to hold in the pressure, and I put it directly into the fridge at the end of the second ferment, and then take it out and bring to whatever destination. My thought is, as long as your syrup type bottle is strong and tightly-sealed to hold the pressure/carbonation, it would be fine!
https://www.ebottles.eu/en/produit/clear-glass-bottle-1000ml-syrup-neck-28pp-tamper-evident-470gr-cylindrical-xpr15517.html
something like this.
I am currently doing the same with the flip top ones but they are very expensive and sometimes I don’t get them back
I think as long as they can hold pressure, they should be fine then! I trust that you will test it. Oh, I totally hear you about not getting back the expensive flip-tops.
Hi there, have you ever used pomegranate molasses for your second ferment? I have added 1/2 tablespoon to 1 pint of kombucha
No, I haven’t. I have only used regular molasses for 2nd ferment. Pomegranate molasses sound yummy. Thank you for sharing!
Thanks Yang, i really enjoyed this article. i’ve been making Kombucha for about a year now, and have always done a 2nd ferment with various fruit, herbs, ginger, etc. i do the 2nd ferment in a jar with fabric covering the top so it can breathe. a new scooby always grows on the top of the 2nd ferment, with fruit embedded in it – i discard. after the 2nd ferment i filter and bottle in air-tight flip top bottles and let stand at room temp. the fizz develops pretty well during the time the shelf time, and i even had a bottle explode once, so i’ve learned to fill them pretty full, so there no additional oxygen for fermentation, and i burp them regularly. There is one problem however – the biologic processes still continue in the sealed bottles, with little scoobies growing in them. these have no taste, but are a bit odd in the mouth. given that after the second/fruit ferment, the kombucha is filtered before bottling, is there a way to prevent the scoobies from growing in the sealed bottles waiting to be drunk? i notice that when i buy kombucha in the store, there may be a little bit of flaky solids, but never any scoobies.
Hi Kim, I totally hear you! Sorry about the late response – I wanted to post this question to my other fermenter friends to see if everyone have the same experience as I do. So yes, as far as I know growing extra tiny scoby after bottling is totally normal and not preventable. I believe it’s a sign of healthy culture. The speculation is that commercial kombucha may have the specific strain of bacteria that contribute to scoby growth suppressed. It seems to be the only reasonable guess, but I have no proof for it. Hope the confirmation that everyone else have the same experience as you helps a bit. 🙂 Thank you for visiting my blog!
Hi! Great article
At the end of the second fermentation can I transfer the kombucha from the flip top bottle to a regular glass bottle then refrigerate? Or does it have to remain in the flip flop bottle ?
Thanks