This is a follow up post to the original Scaling Up – Brewing 5 Gallons of Kombucha at Home (which I forgot to continue updating). I don’t know why I never finished the original post, but here we are now, almost 1 year later and I’m digging back through my notes and pictures to see what I can piece together.
After going back and trying to dig through my notes and pictures, I realized that I did a terrible job in taking notes and that pictures are very few and far between as well. I may have brewed this first 5 gallon batch of kombucha with no expectations, or maybe I was just too excited to get it going, so I didn’t take time to take notes and pictures. Either way, what you’ll get here is the best I can put together from memory and the few pictures that I did take.
The first part of this post ended up about 5 days into fermentation and at that point, the scoby had risen to the top and a small layer was starting to form on the surface. I do remember that it took quite a while for the scoby to really form on this batch and start the fermentation process. I think this was partially due to the fact that I didn’t have enough starter tea to pour into the batch along with the scoby.
The scoby is generally known to do all of the fermenting in kombucha, however the starter tea definitely has its purpose as well. Starter tea is basically just healthy, unflavored, fermented tea – kombucha. Adding starter tea to a new batch of kombucha has two main purposes:
- To lower the overall pH of the batch and make it more acidic
- To introduce any additional microbes that might not be present in the scoby
I believe it was the lack of a sufficient amount of starter tea that was the reason it took this batch so long to start (and finish) fermenting. Suggested amounts of starter tea are about 2 cups per gallon of kombucha which would indicate that this batch would have required about 10 cups of starter tea. I don’t have notes, but I would be surprised if we added 3 cups of starter tea to this 5 gallon batch.
Nonetheless, it did finally make it through fermentation after 3 weeks and I was able to add some fruit to it. The batch started on September 3 and I pulled the scoby and added fruit on the 24th.
3 full weeks of fermenting. In most cases, if a normal amount of starter tea was used, I think we would have been left with vinegar after 3 weeks, however since we didn’t have the right amount of starter tea, I think the extra time was necessary. I’ve read that kombucha can ferment for anywhere from 7 to 30 days with the sweet spot being in the 7 to 14 day range. Beyond that, you start to get a very vinegary flavor.
Removing and Storing the Scoby
After primary fermentation is complete, you want to remove the scoby so that you can add your flavoring and let the kombucha.
At this point, many will drain their kombucha into smaller bottles that are pre-filled with fruits, herbs or other flavorings and allow the kombucha to naturally carbonate, but since we’ll be kegging this batch, we’ll continue our secondary fermentation in the same vessel.
If you’re interested in bottling your kombucha, check out the link above.
To remove the scoby, washed my hands really well and barehanded the thing. If you’ve never handled a scoby (which I hadn’t), you’d likely be surprised at how dense and durable it is. To be honest, I thought the thing was going to tear apart upon handling it. Since the final scoby was about 15+ inches in diameter, my original plan was to take a circular cookie cutter and cut small circles out for storage and later use. That proved to be pretty difficult, so I had to get a knife involved.
Once the giant scoby had been scaled down, it was all added to a large jar and topped off with some of the kombucha from this current batch. Then into the fridge for storage and ready for the next batch. The next batch came sooner than expected and we used this to do a batch of raspberry kombucha at the office.
Adding Fruits, Herbs and Natural Flavors to Kombucha
With the scoby removed, it was time to add some flavor to this batch of kombucha. In our first couple small batches, strawberry was a hit and we still had access to some fresh strawberries, so that’s what we did.
If memory serves me correctly, we added 1 cup of sliced strawberries per gallon of kombucha, so approximately 5 cups in total.
Now, if we had added the fruit into bottles and were going to let the kombucha naturally carbonate, it could take up to a week or more. Plus, you have to be cautious that you’re not creating “bottle bombs” and take care to “burp” your bottles from time to time to make sure that they’re not becoming over carbonated.
This is why I prefer kegging kombucha.
It’s much easier to flavor the kombucha in the same vessel that it was brewed in. This way, you can sample as day to day as the fruit flavor is extracted and when you hit the taste profile that you like, you can move your kombucha into a keg.
See the video below, this isn’t this batch of kombucha, but we took a similar process in our next batch which was brewed at our office. Rather than using strawberries, we used raspberries to flavor the kombucha. Using our large brew system, the process was simple – remove the scoby, add the fruit and then wait. If you watch the video, take notice of our “scoby scoop” that we use for removing the scoby, rather than bare handing it like in the picture above.
Kegging Kombucha
Honestly, kegging kombucha is simple. I wish I would have taken more pictures of the process, but as I’ve said before, “If you can fill a jar, you can fill a keg”. So since there are no pictures, I’ll sum it up quickly, filling your keg with kombucha is as easy as draining your brew vessel into the keg of your choice.
Here’s one picture that I did happen to take, the fermentation vessel after being emptied into a keg, just strawberries remain. One thing that I need to look into is if this fruit can be used after being fermented. Truth be told, I tried a strawberry and it was, well… a bit tangy. I’m not sure if that’s the right description, but it was surprisingly flavorful given its appearance, but it had taken on quite a different profile than how it had gone in.
The strawberries sat in the kombucha for just 4 days prior to being kegged. Amazing to see how much color they lose over such a short amount of time.
This isn’t from this batch of kombucha, but shortly after we did this batch of strawberry kombucha, we decided to brew a batch of raspberry kombucha at our office. You can check out the process of kegging kombucha and serving kombucha on draft in the video below.
Pouring Kombucha on Draft
After being kegged, you can essentially start pouring kombucha on draft immediately, however I prefer slight carbonation in my kombucha. This is another benefit of kegging verse bottling. Once the kombucha is in the keg, you can hook it up to CO2 and force carbonate it very quickly if you’d like by applying a very high pressure, or you can hook it up at a lower/serving pressure and let it carbonate slowly over a period of a few days. If you can wait, this method is a little easier as it helps prevent over carbonation.
How about you, do you prefer kombucha to be flat or a little effervescent?
Let us know in the comment section below.
Final Thoughts and Takeaways
Overall, I was very happy with the way this batch turned out. It was extremely drinkable and the whole family loved it.
I especially loved having it on tap in the keezer. It’s so nice to have kombucha on draft at home. I can’t tell you how many times I opted to pour a nice tall glass of kombucha rather than having a beer.
Things that I’d do different next batch:
- Use more starter tea. If 2 cups per gallon isn’t available, consider adding some vinegar to help adjust the pH.
- Try to incorporate a heater to help keep temperatures up. I think the temp may have gotten a bit too low some evenings which could have played a role in the longer fermentation time.
- Take more pictures to share with any of you who have read to this point!
Photo and video links
How to Add Natural Fruit Flavor to Kombucha During Second Fermentation via Keg Outlet on YouTube
How to Keg Kombucha and Serve Kombucha on Draft via Keg Outlet on YouTube
Photo by Candice Picard on Unsplash
Photo by Whitney Wright on Unsplash
Is there a risk that the SCOBY continue to grow in keg ?
Because when I put my kombucha in bottle (after removing the SCOBY of course), even after filtering with coffee filter, A new SCOBY is growing in my bottle (kept in fridge).
So, I’m a little afraid that this new SCOBY could blocked my tap…
I’m French, so I’m sorry for mistakes in my message…
Thanks
Hi @disqus_S871febUXB:disqus – thanks for taking the time to comment!
In my experience, refrigeration has always seemed to stop fermentation and the growth of a new SCOBY. In our experience with kegging kombucha, we have not seen any new SCOBY growth – I believe this is partly due to the refrigeration and partly due to the fact that the keg is pressurized with CO2 – there is not oxygen available for the SCOBY to grow.
Tank you for this quick answer. I will try this soon !
Anyway, it is strange that you’ve never seen a new SCOBY growing in your fridge.
I have a new one every time, in less than a week…
However it might not be a real SCOBY but only part of it because it does not growth on top (as SCOBY does) but at the bottom of the bottle (it might be only part of the bacteria of the Real SCOBY…).
Nice write up. I’m thinking of scaling up and I also have the SS Brew Bucket. Did you leave the cover on during 1F, or did you use an alternate cloth covering, similar to what you’d use with small batch brews?
Hey @disqus_Ly5HKuSoNl:disqus – we used a cloth cover that was held in place with a large rubber band. Your kombucha still needs to “breath”. Once the first fermentation was complete, we added flavoring and placed the original brew bucket lid with an airlock.
That makes sense. I’ll fashion a cloth cover for the opening and thanks for the reply.
Some good advice there. I am just starting to keg kombucha. Maybe I’m wrong, but after F1 I put it into a keg with flavouring (fresh pineapple in a mesh container). For F2, I left the sealed keg out at room temperature for 3 days. I did it this way because I like natural carbonation and a little bit of alcohol production. The keg is now chilled, but the next step I am not sure about. What psi should I charge the keg with to serve? And do I need to charge the keg well before I serve?
Some good advice there. I am just starting to keg kombucha. Maybe I’m wrong, but after F1 I put it into a keg with flavouring (fresh pineapple in a mesh container). For F2, I left the sealed keg out at room temperature for 3 days. I did it this way because I like natural carbonation and a little bit of alcohol production. The keg is now chilled, but the next step I am not sure about. What psi should I charge the keg with to serve? And do I need to charge the keg well before I serve?
@negrotski:disqus hook it up to CO2 pressure anywhere from 6-12psi. The higher the PSI, the more carbonation you’ll push into the solution. Personally, I prefer my kombucha only slightly effervescent, so I generally keg at about 6psi or so.
Ok great, thanks for the tip!
Thanks for the info, Brendan! I am considering a similar process to @negrotski:disqus with natural secondary fermentation directly in the kegs; the main point being the difference in mouthfeel from forced carb. Instead of serving the straight from the keg, I would like to bottle the kombucha from the keg after chilling. I will fill the entire keg into bottles all at once and am considering using a beer gun to get the booch into the bottles.
I have three questions:
1) Do you think I need a CO2 tank to then force the naturally carbonated Kombucha out of the keg and into bottles? I imagine problems with a growing keg-headspace while filling.
2) If so, will the added CO2 get into the Kombucha or will the bottles mainly contain the natural CO2 already present in the Kombucha itself?
3) I will need to filter the Kombucha on the way from the keg to the bottle due to yeast buildup during F2 and potential sediment from flavoring ingredients. Do you have suggestions for a setup? Maybe a catridge filter inbetween the keg and the beer gun?
Thanks for your help!
Hi @inkyleaf:disqus , thanks for the comment! I’ve put some thoughts/responses below to correspond with your 3 questions.
1) Absolutely. I don’t think the carbonation generated naturally will be enough to force 5 gallons out of the keg and into bottles…. though I have never tried anything like this, so I could be wrong.
2) If you just pressurize with CO2 when you plan to transfer from the keg to bottles, then no, there won’t be much (if any) additional CO2 making its way into the solution. The only way you’d see that happen is if you left it under CO2 pressure for a long time, or at a high pressure.
3) A cartridge filter could work, but may be expensive. This option might be more economical: https://www.kegoutlet.com/cb-f-cold-brew-coffee-filter-for-ball-lock-kegs.html
Thanks again for the comment. Good luck, and let us know how it goes! If you document it, maybe you’d like to do a writeup on our blog! 😉
Amazing information, thanks again Brendan! This is exactly what I was hoping to hear 🙂 and will definitely be trying it out. I´ll keep it documented and of course I would be happy to do a writeup. First I need to assemble some equipment…I´ll keep you posted.
Hey there Brendan,
I am just about ready to try this out, but I have a follow-up question:
What if the ball-lock-disconnects clog up when moving the secondary-fermented booch out of the keg and into the bottles? A fellow brewer mentioned that he had problems with this even with forced carb, so I am expecting that with a full-on secondary fermentation in the keg, I would have tons of yeast just waiting to clog up that disconnect. Is there something I can do or a piece I can install to keep the disconnect clear within the keg?
Thanks!
It’s for this reason, we usually recommend a separate fermentation vessel. Yeast, small sediment and particulate generally shouldn’t be a problem, but if you get any larger stuff or parts of your SCOBY left in there, you could have some problems.
Gotcha. We are going to give it a try and see what happens. I’ll report back in a few weeks!
Thanks!
Nice thread here! I’ve seen floating dip tubes at the home brew store. They pull from the top vs the bottom. Quick fix is cut the dip tube/loose efficiency at the bottom.
I am on day 4 of my five gallon batch in a similar fermenter, and I did use 10 cups of starter and started seeing the new layer of scoby pretty much the next day, so that would confirm why yours took so long. I’m also using a heating wrap with a temperature regulator/sensor in thermowell to keep the brew at a steady 79 degrees, so I’m thinking it’ll take the typical 7-10 days that you mentioned.
Another thing I noticed, since I’m thinking about how I want to do my flavoring, is you left the fruit in for days after you were done fermenting, but even if you remove the scoby, it still exists in the liquid, so essentially you let it go another 4 days of fermentation while flavoring? I’m thinking of just added juice in right before kegging.
HI, a quick question, i have force carbonate my kombucha in keg for couple of days and taste and it’s perfectly carbonated. Then I bottle them up and keep them in fridge. After 1 night i decided to taste the kombucha from the bottles and they run out of carbonation. Is there anyway to solve this problem? i would like to keep my kombucha in bottles and send them to friends and family to enjoy. Thank you
Always a tough proposition. Try a counter pressure bottle filler?
Hi! Great write up!
I’m just wondering, during your 2F stage with the strawberries (or raspberries) did you leave the vessel without a lid and just some cloth (as you would during 1F stage) or did you put a lid on the pot, and if so, does it need to be sealed airtight with any clamps
@crazyry:disqus we put the lid on the fermenter along with an airlock as there is still some active fermentation during that time. I think if it were to be airtight/clamped, the booch would actually pick up a bit of carbonation.
To be honest, even without the fully sealed lid and the airlock, there was some perceived effervescence in the booch prior to kegging.