What is the Point of Second Fermentation for Kombucha: Health Benefits, Flavor, & More!
For those of you who may not know, kombucha second fermentation is an optional step in the kombucha making process. Second fermentation is the process through which your kombucha can be flavored, carbonated, and more! While it is not a necessary step and plain ‘ol primary fermented kombucha is wonderful for you as well, we are big fans of second fermentation and think you will be too by the end of this article!
The Obvious (& Palatable!) Benefits of Second Fermentation
Once primary fermentation is complete, you will remove your SCOBYs (symbiotic cultures of bacteria and yeast) and have the option to take your kombucha on the journey that is second fermentation. SCOBYs are present throughout the entire primary fermentation process, and unfortunately they are rather fragile; straying from the status quo during the primary fermentation process can ruin a batch of kombucha and even destroy the SCOBY! The primary fermentation process is also aerobic as the SCOBY requires oxygen to conduct its magic. This is why we cover the fermentation jar with a breathable coffee filter or cloth. Luckily, second fermentation is SCOBY-free, allowing us to experiment and reap many benefits without risking the health of our kombucha and SCOBY! The most apparent of these benefits are…
Flavor!
Second fermentation consists of flavoring your kombucha in a number of different ways! To begin this process, you will add your kombucha to your choice of fruits, juice, herbs, spices, vegetables, extracts, and more! This means you can significantly diversify the flavor of your kombucha! As an added bonus, we will continue to ferment the kombucha after adding these flavors. The yeast remaining in the kombucha will consume most of the sugars that we add, leaving us with a healthier end product. If you aren’t enticed by the myriad of potential flavors you can add, you should know that the yeast also releases CO2 into your kombucha as a byproduct of consuming the sugar. This brings us to our next point…
Carbonation
The CO2 (carbon dioxide) released into the kombucha is actually what carbonates it! So, unlike sodas and many other popular beverages which are artificially carbonated, our kombucha ends up being naturally carbonated through the second fermentation process! Keep in mind you will need to add some form of sugar prior to the second fermentation process in order to fuel the yeast; if you would like to flavor your kombucha with veggies or keep the flavor profile basic, you can achieve carbonation by simply adding approx. 2/3 tsp. of sugar.
As mentioned before, the primary fermentation process is aerobic. To the contrary, second fermentation is anaerobic; our kombucha and added ingredients must be placed in an airtight bottle and fermented for 1-14* more days. This keeps our carbonation sealed within the bottle! In fact, so much carbonation can build up that you will want to “burp” it (lift lid to release excess pressure) daily during second fermentation to avoid an explosion! *The variation in the second fermentation process is explained by variables such as temperature, ingredients added, and personal preference!
Health Benefits of Second Fermentation
Nutrition of Added Ingredients
One of the more obvious health benefits of second fermentation is the addition of nutritious fruits, herbs, and more! From berries to chia seeds, kombucha will appreciate all of the healthy foods you “feed” it. Fermentation also makes foods easier to digest, meaning you might end up getting even more nutrition out of your added ingredients than you would have if you ate them raw! Fermentation also preserves food, meaning you can eat the fresh fruits and veggies you add to your kombucha even if it has been sitting in the fridge for weeks. It doesn’t get any better than that! But wait, actually it does…
Less Sugar
As mentioned earlier, yeasts in kombucha consume sugars during both primary and secondary fermentation. Since secondary fermentation means fermenting your kombucha for longer, it also means additional sugar is consumed by the yeasts. The longer the fermentation period, the less sugar your end product will have! This makes second fermentation kombucha an even more attractive option for all health-conscious individuals. It is also a delicious and much more nutritious alternative to soda and other high-sugar drinks for diabetics and others watching their sugar intake.
More of the “Good Stuff” from Fermentation!
The fermentation process produces countless probiotics, beneficial acids, and antioxidants that can be found in kombucha. During second fermentation, many of the yeasts and bacteria responsible for these wonderful things remain in the kombucha even after the SCOBY has been removed. They continue to work the parts of their magic that can be conducted anaerobically, meaning the end product will have more of these beneficial byproducts. Health benefits of these compounds include improved digestion, detoxification, increased energy, boosted immune system, defense against cancer-causing agents, and even more! Kombucha gives a new meaning to the word Superfood! (Or Superdrink?)
Boozy Kombucha
One thing to be aware of with second fermentation is the fact that the alcohol content in your kombucha can be increased somewhat significantly. Upon consuming sugar, yeasts produce ethanol in addition to carbon dioxide. During primary fermentation, bacteria converts most of the ethanol to organic acids through an aerobic (oxygen-requiring) process. Once we move kombucha to sealed bottles for second fermentation, there is a very limited amount of oxygen available to the bacteria. As a result, the bacteria cannot convert most of the additional ethanol produced during this stage. This means that the alcohol content of the kombucha increases as the kombucha is bottled for longer periods of time; especially if the yeasts are given some form of additional sugar to convert during second fermentation.
This is generally not something to be too concerned about; if you conduct second fermentation for a standard amount of time, the alcohol content of your kombucha should not exceed 3% ABV. However, if you make it your goal to increase the alcohol content of your kombucha, you can quite possibly reach an ABV as high as 5-6%! This would involve efforts such as increasing the yeast content of your SCOBY, adding more sugars prior to second fermentation, and conducting second fermentation for an extended period of time.
Give Second Fermentation a Whirl!
All that’s left to do now is embark on your second fermentation adventure! Do some reading about all of the wonderful options you have for flavoring your second fermentation kombucha! If you have not yet completed the primary fermentation process or haven’t started your kombucha journey at all, you will want to review the entire process first.
Have any questions or comments? Please let us know using the comments below! Thanks for learning with us today and we wish you and your kombucha all of the best! 😉
Hello,
I am very new with this all process of fermentation… I just started 3 weeks ago, and I have bottled my first fermentation and place the bottles in the fridge.
The Ph was 2.5 – Is that bad?
Should I put back the tea in a Gallon jar and continue to the second fermentation or is it too late?
Thank you
Hi Nadine!
A pH of 2.5 on your fermented kombucha is great! You want the kombucha’s pH level to be between 2.5 and 3.5 after the first fermentation.
I would recommend using airtight glass bottles for second fermentation. If you use a gallon glass jar, you will not be trapping most of the carbonation.
If you already had the bottles in the fridge for some time, I would recommend drinking this batch plain and planning to do a second fermentation on your next batch IMMEDIATELY after the first fermentation– you do not want to place the kombucha bottles in the fridge between first and second fermentation.
I hope this helps! Best of luck!
Kristie @ Bucha Brewers
[…] If you would like to learn more about the benefits of second fermentation, check out this article! […]
I was told that I may have candida and not to second ferment with fruit etc. is there any way I can get fizz into kombucha without second fermenting or adding more sugar?
Hi Cathryn!
If you mean candida medically, we would recommend speaking with your doctor. We are not licensed medical professionals.
Unfortunately, carbonation in kombucha is driven by yeasts. You could try bottling your kombucha on the earlier side (7-10 days) and letting it sit at room temperature in airtight containers for a few days. The kombucha needs to be sealed to gather carbonation, and unfortunately only the yeasts operate in an anaerobic condition.
I would also recommend looking for a home-brewing/fermentation group online if that is an option. We have no experience with candida, but you can likely find another kombucha home-brewer with candida in a kombucha fermentation group! They might be able to advise on what has worked for them. Best of luck!
I am new to making Kombucha. In reading about the alcohol content present in the 2nd fermenting process, is it safe for my kids to drink?? I have my first batch brewing and will be ready to do the 2nd ferment in the next couple of days. Our goal was to do a 2nd ferment because we love the carbonation and flavors, but if it has alcohol is it safe for kids to consume? I’m confused…help!! 🙂
Summer~
Hi Summer,
Thanks for reaching out! We have the perfect article for you: https://buchabrewers.com/kombucha-for-kids-is-it-safe
You can manage your brew to keep alcohol content very low– the article goes more in-depth! Happy brewing! 🙂
Of course, the alcohol produced in fermentation isn’t inherently dangerous to children anyway.
Many cultures (other than American) encourage their children to consume alcohol at very young ages (in a dilute).
Due to the fact that kombucha rarely reaches 3% (usually around <1-1.5%) its perfectly "safe". If a child (or adult) consumed enough kombucha to even feel the alcohol content they would have other problems to deal with in the restroom.
Thank you for your opinion, Jay!
I’ve been brewing kombucha for 3 months. Done 8 or so successful 1st fermentation but cannot seem to get 2nd fermentation to carbonate well. I’ve tried multiple ideas, bottles and times. Only get a slight barely fizz. No pop on opening bottle. I’ve tried adding fresh fruit, sugar, raisins, loose fruit tea with sugar, quart jars brewing flip top bottles, 70+degrees, dark, 3days to 7 days. Ginger beer won’t fizz either. Tepache is better but still not really fizzy. ???
Hi there, I’d definitely recommend trying to implement some of the changes in this article: https://buchabrewers.com/kombucha-carbonation-10-ways-to-get-more/
This could help you to identify problem areas as well. Best of luck!
Hi! My first fermentation already resulted in quite a bit of carbonation, does this Mean i shouldn’t do a second one? Of perhaps keep it shorter? It’s my first time and I’m a little afraid of any possible exploding of my bottles. Thanks!
Hi there!
You can certainly still do a second fermentation– this is a pretty nice “problem” to have! 🙂
I would just recommend checking after 24 hours to “burp” your bottles and release any excess carbonation. You could start with a short 48-hour second fermentation & allow bottles to cool in the fridge before opening
Happy Brewing!
i make my 2nd brew in 2-2gallon jars, and end up with new scoby loaded with the ginger bits, is this a new event or does it happen often of never or what?
Hi there, were you brewing with ginger bits in your first fermentation jar? If so, that is the issue. First/primary fermentation should not have any added ingredients. Flavoring ingredients should only be added during second fermentation, after your SCOBY and starter tea has been removed. Our kombucha brewing instructions go into more detail on the division of these processes.
Hello! I’ve been brewing kombucha for a number of months now. Most recently I have been down in Guatemala and have found the second ferment with fruit less successful- very low sugar and kind of tasteless. I just read in the article above that I should add a little more sugar?
Hi Ann!
You are correct– if your 2F is turning out flat or lacking flavor, I would recommend adding more sugar (in one form or another).
Generally, I would recommend fruit. If you have not been a fan of your fruit ferments and have been adding as much as 1/4 cup of fresh/pureed fruit, I would recommend trying fruit juice & adding at least a couple tablespoons to each airtight 16 ounce bottle. If you are not yet using truly airtight glass bottles, this could be your culprit as well!
Hi. I am on my second fermentation and I don’t have much carbonation. I didn’t add much fruit juice (our own pressed cider). I am only 3 days into my second fermentation and I was wondering if I should either add more cider or more sugar at this point. Is it too late?
Thanks!!!
Hi Linda! You could certainly add more juice or sugar at this point, but if you are happy with the flavor & sweetness level at present you may want to make some other changes to get more carbonation in your future 2F kombucha (click this link for a kombucha carbonation troubleshooting article).
Some quick wins to check on: are you using completely airtight bottles for 2F? are your bottles stored in a dark space? Are the bottles in a warm space? Yeast in your kombucha thrive in warmer temperatures–you can even try placing your 2F bottles on a kombucha heat mat for fast & significant results- just make sure to carefully “burp” your bottles daily if you do so!
Sorry for the late reply & I hope this is helpful for future reference! Feel free to reach out with any additional questions. Happy brewing! 🙂
For plain kombucha’s 2F you recommend 2/3 tsp sugar added to each bottle or a one gallon batch before bottling. Sorry I’m new! Thank you!
Hi there!
This refers to adding 2/3 tsp sugar to 16 oz 2nd fermentation bottles when you are not adding another source of sugar (such as fruit). I hope this helps!