A (Slightly Schizophrenic) Kombucha Primer

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I've always enjoyed fermenting things, ever since I made my first hard cider when I was 19 and not cool enough to have friends that were old enough to buy me beer... er, I mean, 21 years old and not a day younger. I am fascinated as much by the process as I am the finished product. Cider, beer, wine, kimchi, sauerkraut, kvass, mead, sake, pickled vegetables; all a combination of science and culinary art which I can take part in right in my kitchen.
When one of my friends told me I could ferment sweet tea, I thought ew I have to try that!

Glass Of Kombucha
I have been an avid beer brewer for 8 years now, all the while dabbling in other various fermented foods and beverages. The only thing I make more of than beer is kombucha. It's easy, it's cheap, it's delicious, it's good for you, and best of all, I can drink it at work!
What is it?
Glad you asked! Kombucha is a fermented tea-based beverage that-
How's it made?
Er, well, I was getting to that. Kombucha is made by fermenting sweet tea with a SCOBY-
Wait, what's a "SCOBY"?
Again, if you'd let me finish... SCOBY is an acronym for Symbiotic Culture Of Bacteria and Yeast, which is just a fancy way of saying a combination of various microorganisms that work together to ferment sugars into alcohol and various organic acids-
What's it taste like?
PLEASE stop interrupting me, imaginary hypothetical reader, and I'll get to that. Kombucha is lightly sweet, effervescent, and mildly tart, with a slightly vinegary taste, not unlike a sour beer. It can be an acquired taste for some, and some (like SWMBO) find it disgusting, but those of us who enjoy fermented foods such as sauerkraut tend to find the taste quite wonderful.
You can ask another question now.
Oh, am I allowed to talk now? Or are you just going to get all snippy again?
Look, I'm sorry, it's just kind of irritating when you keep cutting me off mid-
-sentence. Like that Plus, I had a hard day at work, then problems at home, and my blood-sugar is kinda low. Look, can you please just ask your next question so this article can progress? Right now it's going nowhere fast.
Fine. Where do I get ingredients to make kombucha? My homebrew shop, perhaps?
Good question, mysterious disembodied voice! Yes, a lot of homebrew shops now carry everything you need to make your own kombucha, from SCOBYs, to loose leaf tea, to starter teas, to fermenters and bottles. There are also dedicated kombucha-brewing shops as well that specialize in selling kits and ingredients. But I'm going to let you in on a little secret.
What is it?
Lean in closer, and I'll tell you.
You're not going to try and kiss me, are you? Because I'm not into th-
What? No! Fine. I was just going to say that you can find everything you need to start brewing kombucha for cheap at the grocery store. No need to buy dehydrated SCOBYs or fancy equipment kits. After a small initial investment, you'll be drinking your own homemade kombucha for mere pennies each.
Okay, what do I need?
You'll need the following equipment:
  • A small stock pot, large enough to bring 1/2 gallon of water safely to a boil.
  • A 1.25 gallon or larger wide-mouthed glass jar, for fermenting. I got one from Wal-Mart for $12 that has a spigot at the bottom, which really comes in handy at bottling time.
  • A rubber band, large enough to fit around the neck of the jar.
  • A clean cloth, to cover the opening of the jar.
  • A spoon, for stirring.
  • A measuring cup. For measuring things.
  • Enough bottles to hold 112 ounces of kombucha. Some people like to use beer bottles for this, but I prefer 16oz wide-mouth glass bottles. I just reuse old commercial kombucha bottles.

What about ingredients?
Yes, you will also need the following ingredients:
  • 8 single-serve tea bags, unflavored (no Earl Grey, etc). I buy the cheap store brand, 100 bags for $1.99.
  • 1 cup of sugar. Plain white, no brown or powdered. Organic is fine, if you hate money.
  • 1 gallon of water. I shouldn't need to clarify this.
  • 1 bottle of commercial unfiltered, unpasteurized, unflavored kombucha.

That's it? Wait, what about the SCOBY?
Yup, that's it. We're not going to buy a SCOBY; we're going to grow our own.
Okay, I just bought all this crap you listed, what do I do with it now?
Piece of cake. I'm going to teach you how to brew a weekly batch of kombucha to feed your new daily drinking habit.
1) First, add 1/2 gallon of your water to the stock pot, and put it on high heat on the stove. Save the other 1/2 gallon in the refrigerator to chill.
2) When the water comes to a boil (the water in the stock pot, and not the water in the fridge, ideally), remove it from the heat source and add the sugar, stirring until dissolved.
3) Once the sugar is dissolved, add the tea bags and steep for 5 to 10 minutes.
4) Allow the sweet tea to cool down to room temperature. The not-boiling fridge-water can be added to accelerate the process.
5) While the tea is cooling, clean the glass fermentation jar. As in beer brewing, cleanliness is important in kombuchery (I think that's a word), but you don't have to be as anal about sanitation, due to kombucha's naturally low pH and aggressive microbes. While I meticulously sanitized my equipment for my first batch, I haven't sanitized my fermenter for any subsequent batches. As with sour beers, infection is kind of the point.
Just trust me. Moving on:
6) After the tea has cooled, transfer it to the glass jar, and add the remaining water, if you have not done so already.
7) Pour in the bottle of commercial kombucha, swirling to make sure you get all of the dregs out of the bottle and into the tea.
8) Cover the opening with a clean towel and secure with the rubber band. This will allow the kombucha to breath, while keeping dust and particulate out. Store in a warm, dark area of your home (I keep mine at the top of the pantry) for 2-4 weeks, checking on it once or twice a week.
Okay, so I can drink kombucha now?
Almost. We're just growing the SCOBY right now.
Patience. Don't worry, we're nearly there. Over the course of the 2-4 weeks, you will see a film develop over the top of the tea. That film with continue to get thicker and thicker until it forms a large, rubbery puck that floats on top.

Ew. That looks like some sort of alien jellyfish. No way I'm drinking this stuff now.
That, my non-existent friend, is the SCOBY.
THAT'S the SCOBY?!?!?
Uh-huh. And now that we have it, we can start the real fun.
Okay, so what do I have to do now?
Pretty much the same thing we did before. By now the tea inside the fermenter is likely to be too tart and acidic to drink, because it has been sitting for too long. Go ahead and transfer the SCOBY to a clean plate, and dump the fermented tea out. Replace it with a fresh batch of sweet tea, following the same steps 1 through 7 above using the same ingredients. Now, gently place the SCOBY back into the jar. It should float on top, but if it sinks, don't worry about it. Cover as before, and wait just one more week.

Fermenting Kombucha
Wake up. It's time to bottle the kombucha.
Well, it's about damned time!
Now that spigot is going to come in handy, if you were smart enough to buy a jar with one. Before bottling, go ahead and prepare your next batch of sweet tea to ferment. I'll wait.
Okay, got it.
Good. Now, gently transfer the fermented tea to your bottles. You should have enough kombucha to fill seven 16oz bottles (that's one for each day, for those keeping score at home), with another 16 ounces or so to spare. You can either throw these in the fridge for immediate drinking, or let them sit at room temperature for a few days to build up effervescence. Draw off an additional 16 ounces to use as the starter tea for your next batch. No more having to buy commercial kombucha for you.
Good. That stuff is expensive. $3.50 a bottle? I can buy beer for cheaper!
Right? Next, remove the SCOBY, and dump in the replacement sweet tea, and the 16 ounces of starter tea you saved. Return the SCOBY to the jar, cover, store, and repeat the process every week.
Kombucha forever!
And how! Now, keep in mind, this is just a beginner's primer. Like beer, kombucha is open to variation and experimentation. For example, I like to try using different teas (half green, half black is my favorite so far). Try adding a couple ounces of fruit juice to each bottle, or sliced ginger, or hops. If you want a more highly-effervescent product, you can add a small amount of simple syrup to each bottle.

Sweet. And you said I could drink this at work, right? But I thought it had alcohol in it?
Yes, there is a small amount of alcohol produced during fermentation, but it is only a fraction of a percent. As such, it is not actually considered to be an alcoholic beverage, which is why you can buy it from the store without having to show ID.
Right on. Anything else I should know?
Probably. But my hands are getting tired from all the typing, so I'll keep it brief, and if you're lucky I won't leave anything important out. A few things:
1) Acidity - The longer you let the kombucha sit in the glass jar, the stronger and more acidic it will become. I have found ~1 week to be the sweet spot for me, but this will largely depend on the temperatures in your home, the makeup of your tea, and the strength of your culture, and of course your personal tastes. I would caution against drinking tea that is too old and strong, as some studies suggest this can lead to health complications due to excess acidity.
2) SCOBY Growth - The SCOBY will continue to grow with each subsequent batch. Consequently, you will need to trim it from time to time. Simply peel off the top few layers. These can be discarded, given to a friend, or unceremoniously thrown on top of your boss's desk, along with those damned TPS reports he wanted so bad.
3) Mold - Kombucha is naturally pretty good at keeping unwanted organisms at bay because of it's acidity and bacteria/yeast culture, but one thing you will need to watch out for is mold. If you see anything furry growing on top of your SCOBY, then it's best to play it safe and dump everything, sanitize thoroughly, and start over. If you're reasonably careful about cleanliness, you probably won't have an issue with mold contamination, but it can happen.
4) Cross Contamination - Just like in sour beer brewing, it's important to keep your kombucha brewing paraphernalia segregated from your beer stuff. We are dealing with bacteria, after all. Otherwise, you run the risk of accidentally souring a beer that you didn't want to be sour.
Are you done yet? This article is entirely too long, and this schtick with you talking to yourself has long since lost its novelty, you hack.
There's no need to be rude. Yup, that about wraps it up. I hope this article will encourage you to try your hand at brewing kombucha. If you have any questions about kombucha, feel free to shoot me a PM, or check out the kombucha sub-forum.

Author Bio:
Hunter La5 is a person, who exists. Sometimes he writes things and stuff, but it's mostly erotic HBT moderator fan-fiction, and should never see the light of day. He enjoys drinking beer and kombucha, and sometimes makes them too. He spends most of his time in the nether regions of HomeBrewTalk.[URL="//www.pinterest.com/pin/create/extension/"][/URL]
Nice write up! This is exactly how I started a few months ago, although now I use a continuous brew. Everyday I draw off a pint bottle from the bottom spigot, and every other day I make a quart of sweet tea in a mason jar: 1 tea bag each black and green tea, 1/2 cup sugar, and just-off boiling water to fill. I let it sit till I can handle the jar easily, remove the bags, and then shake until the sugar dissolves. I top up with this when there's room to fit the whole thing. Planning on cleaning the fermenter at some point...
I just bottled my first kombucha in beer bottles with some fruit juice for carbonation. The bottles have been sitting for a couple days and now have what appear to be a new Scoby forming on the top. Is this normal? Store bought ones tend to have stuff at the bottom but I would like to avoid drinking the slime if possible.
There are some brands you have to show ID for.. cause it's over half a percent or something. GEEZ GET YOUR FACTS STRAIGHT HUNTER.
Great write up. I am wondering, however, why I need to put the SCOBY as well as the starter tea in every batch. Shouldn't one or the other be good enough?
Does the SCOBY need to be removed or could I drain of the overly-tart SCOBY-making tea and add the fresh cooled sweet tea gently on top. Or is this some sort of "Kombucha heresy"
When filling the bottles does one need to be concerned with oxidation and fill them by adding some tubing to the spigot so they can be filled bottom-up?
Really got the urgent need to get this started ASAP for some inexplicable reason. I've never tasted it but all of a sudden I want kombucha NOW.
I am defeated. I shall now leave HBT in shame and go forth to wander the internetz as an outcast.
That's a good point. For the purposes of this article, I am trying to stick with traditional practices and methods. There are those (myself included) who question whether or not the SCOBY is really necessary for fermentation, or if it is in fact just a byproduct, since most of the bacteria and yeast should actually be coming from the starter tea. I tend to use both in my batches to be on the safe side, but I can say from experience that the starter tea by itself seems to be adequate (my unscientific opinion).
@Gavin C
You could probably just pour the tea on top and be fine. I like to remove it and place it back on top to make sure it's all nice and floaty.
From my understanding and experience, oxidation risk with fermented tea is minimal. I just bottle straight from the spigot, and have never tasted anything resembling oxidation. But then again, my bottles are all drunk within a week or two after bottling. Not sure if oxidation would be an issue if you attempted to "age" kombucha.
Did I miss something about the water? I started reading this from my phone, and thought I saw something about water in the fridge and water to boil. Now that I have it on my laptop, I can only see 1 gal of boiled water, and a mysterious addition of cool water from the fridge. Is it 1 gal total?
Looks like a formatting error. Yes, there should only be 1 gallone of water total. The 1/2 symbol from the original article is not showing up. Those are supposed to be two 1/2 gallon additions (one boiled, one chilled), and not a gallon boiled. I'll see if I can get the head editor to fix that real quick. Thanks for catching that.
Nicely written Hunter and props to your "friend" to be in the same room as you.
I just make a gallon of tea and let it cool overnight, add the starter tea and add the Scoby, I don't pour the tea over the Scoby as I find it sinks when I do.
@Aristotelian Yes a baby will start, after a while you'll never notice it.
@Gavin C , I've never noticed oxidation ether.
I'm a daily drinker and love it, commercial stuff is a rip off, far worse than what you pay for beer.
So, when does the erotic HBT Moderator fanfic hit the front page? We're all dying to see what happens when passedpawn and Yooper get locked in the office on a stormy night with nothing but some scented candles and a keg of Flanders Red. Will Lorena give into the wily ways of The Clearwater Hurricane and his trusty sidekick Roeselare, or will he be rebuffed and forced to return home to his loving wife and hidden dreams of what will never be?
Hey, I just took it straight off the back cover of my advance copy of "Moderated Desire: A Homebrew Choose-Your-Own-Adventure (with recipes in the back)" from the Kickstarter, don't shoot the messenger! ;)
heh heh. Clip the coupon for the decoder ring. 6-8 weeks, but it's worth it. Use it to understand Zuljin's posts.
The function of the extra tea is not to do the fermenting, but to increase the acidity so you don't get other bacteria interfering with your SCOBY.
If you only used starter tea, it would take four weeks to grow a new SCOBY.
Does it matter what brand of Kombucha you use for a starter? I've noticed differences in the bacteria listed on different brands, will they all form a SCOBY eventually? I have access to GT's Kombucha pretty regularly
Interesting/awesome read. I love kombucha but the price is a bummer. A friend tried making it once and it was a flop so I never considered making it myself. I haven't aggressively looked but the brand i usually grab at the grocery is not unfiltered, unpasteurized. But you have re-sparked my interest and I thank you for this write up.
Figure out which brand you like best and use that. Each brand's SCOBY will be a bit different, like beer yeasts are different but with more variables because you're not just using a single strain of yeast but whatever strain/s of yeast and bacteria are in the SCOBY.
and best of all, I can drink it at work!
- Sold!
1 gallon of water. I shouldn't need to clarify this.
- Yet you have a filter pitcher.
(the water in the stock pot, and not the water in the fridge, ideally)
- I reely wish you'd have said this sooner.
The not-boiling fridge-water can be added to accelerate the process.
- Slow down! I'm trolling CL for a new fridge! Hey, there's this chic on here who wants...
kombuchery (I think that's a word)
- If you can spell it and use it in a sentence...
infection is kind of the point.
- I'm a pro already!
dump the fermented tea out
- But I just made it!
but if it sinks, don't worry about it.
- Whut if it floats in the middle and asks for brains?
Now that spigot is going to come in handy, if you were smart enough to buy a jar with one.
- I'm so smart I already had one.
- Amy Lee is so hawt!
(half green, half black is my favorite so far).
- That's whut I've got going now.
which is why you can buy it from the store without having to show ID.
- I don't show ID for anything! I'm a sovereign citizen! You can't force me to show my papers!
but this will largely depend on the temperatures in your home,
- It's room temperature. Is that okay?
Nice write up. Reminded me I've been wanting to try this and gave me all the information I needed to start. Just placed an order for < $20 to get started, thanks!
Gotta try this... after my mead, and two different beers are done fermenting...I got the "Office Space" reference. Now if I could just find my red stapler...
It's my understanding that shelf safe food must be at 4.6 pH or less. Some drinks are much more acidic than that like wine which is usually 3.4 pH, Coca-Cola at around 2.7 and Kombucha which is usually >2.5 pH. As part of HACCP compliance fermentation of commercial Kombucha is stopped at 30g/L acidity (different than pH).
Awesome article! I think I'm going to make my own Kombucha and experiment with different flavors too! I'm curious to see what my final pH readings will be at the end of my 1 week fermentation period.
CAUTION: When performing Kombuchery, it is important to add fresh tea to an existing mixture of already fermented Kombucha so as to keep the resultant PH level below 3.5 to 4.0 range. Not just add a scoby to sweet tea. This acidic mix will make pathogens highly unlikely to take residence, ruin your brew and make one sick. Once it is ready to drink, the PH will be in the 2.8 to 3.2 range depending on your desired taste. If achieving an acidic start is a problem, one can add some pasteurized white vinegar to get the PH below 4.