Once you’ve completed the first fermentation (F1) of your kombucha, the next step is determining when your brew is ready for the second fermentation (F2) or, if you prefer, ready to drink as is. If you’re wondering when your kombucha is “done” and ready to bottle, this guide will help you figure out the right timing based on taste and preference. 

What is Second Fermentation (F2)? 

Second fermentation (F2) is when you flavour your kombucha and seal it in a container to create carbonation. During this phase, fruit or another source of sugar is added to the kombucha, and the yeast continues to consume the sugar, producing carbon dioxide. This process is what gives kombucha its signature fizz. F2 typically lasts 2-4 days at room temperature in an airtight bottle. 

How Do You Know When Your Kombucha is Ready for Bottling? 

The simple answer: It’s ready when it tastes done to you. Here’s how to gauge whether your kombucha has reached the ideal point for bottling: 

  • Smell Check: Your kombucha should have a slightly acidic or vinegar-like aroma, but it shouldn’t be overpowering. 
  • Taste Test: The best indicator is how it tastes. It should have a pleasant balance of sweetness and acidity. If it still tastes too sweet, give it more time to ferment. If it’s reached the right level of sourness for your liking, it’s ready to bottle. 

Pro Tip: Many brewers prefer to bottle their kombucha when it’s just a little too sweet, knowing that the sugars will continue to be consumed during F2. 

  • Timing & Flavour Balance: Remember, you’ll be adding more sugar in the form of fruit or other flavourings during F2, and some of that sugar will be eaten up to create carbonation. Finding the right balance comes down to experimenting with what tastes best to you. 

Can You Drink Kombucha Right After First Fermentation? 

Yes! After about 5 days of fermentation, the kombucha is inoculated with live bacteria and is safe to drink. Some people enjoy drinking it immediately after F1, without going through the second fermentation. At this stage, it won’t be carbonated, but it’s still packed with probiotics and healthy acids. 

If you prefer a fizzy, flavoured beverage, however, you’ll need to go through the second fermentation by bottling your kombucha and letting it sit sealed for a few more days. 

When Should You Start Tasting? 

While you can taste your kombucha throughout the F1 process, it’s best to avoid disturbing the brew for the first few days to allow the SCOBY to form uninterrupted. The first 4-5 days will typically yield a brew that’s still too sweet, so there’s little point in tasting during this time. 

For first-time brewers, it’s a good idea to start tasting around Day 5. As you become more familiar with the brewing process, you’ll develop a sense of how long your kombucha takes to reach the desired flavour. In most cases, brewers don’t taste until Day 7 or 8. 

To taste, you can use a clean straw, ladle, or a wine thief to draw out some liquid without disturbing the SCOBY too much. 

 

Is pH a Good Indicator of When Kombucha is Ready? 

A common misconception is that you can rely on the pH level to determine when kombucha is ready to bottle. While pH is important in ensuring the brew is acidic enough to prevent mold growth, it doesn’t indicate sweetness or the overall flavour balance. The best way to tell if your kombucha is done is by tasting it, not by measuring pH. 

If you’re interested in learning more about pH and how it affects kombucha, you can read my in-depth post on the topic [here]. 

Next Step: Bottling and Second Fermentation (F2) 

Once your kombucha tastes right to you, it’s time to move on to second fermentation. This is where you’ll add fruit or flavourings and seal the kombucha in airtight bottles to create carbonation. The process typically takes 2-4 days at room temperature, after which you’ll have a fizzy, flavourful drink. 

Conclusion 

The key to knowing when your kombucha is ready to bottle is to trust your taste. When the balance of sweetness and acidity feels right, that’s the signal to start bottling. You can also enjoy kombucha directly after first fermentation if you like a less fizzy, unflavoured version. Just remember, the timing is flexible, and finding the right flavour balance is part of the fun of brewing kombucha at home!