Humans have been fermenting beverages for thousands of years, giving us everything from ginger beer to moonshine. But my personal favorite is kombucha.
Just in case you’ve been living in a cave for the past decade or two, kombucha is a fizzy, tangy, sometimes sweet beverage made by fermenting sweet tea with an odd-looking magical creature called a SCOBY. (SCOBY is an acronym for Symbiotic Culture Of Bacteria and Yeast.) It can be flavored with just about anything, it’s chock-full of probiotics, and it’s super easy to make yourself if you’re willing to sacrifice a little space and time.
I am by no means a kombucha expert, but I have been making it myself since 2018, so I’m going to give you a basic overview of the process and share what works for me.
What You Will Need
- Sugar, and it needs to be the real stuff. Depending on how much you start with and how long you let your batch go, you probably won’t end up with much in the finished product. However, the SCOBY needs to eat the sugar in order to ferment the tea. No sugar, no booch. Cane sugar will give you the best results, but there are plenty of options to choose from there. Raw, turbinado, organic, even just plain white refined sugar will do.
• Tea. Any variety of black tea works best, though you’ll want to avoid any added flavors, as they could interfere with the fermentation process. So skip the Earl Grey and the orange spice, and stick with things like English or Irish breakfast teas, Assam, Darjeeling, or even just plain old Lipton. Bagged or loose, either one works. I like loose, but that’s just me.
• A big glass container of some kind. A gallon-size jar is ideal.
• A breathable cloth with a tight weave to cover the top of the big glass container. You want something that will let air flow through, but will keep bugs from getting in. I’ve used old bandannas or cloth napkins, with rubber bands to hold them in place. If you can’t find a rubber band big enough to fit, you could always tie a piece of butcher’s twine or other sturdy string around it.
• Some finished plain kombucha, preferably strong. Yes, you need kombucha to make kombucha.
The Basic Process
First, you’ll put the sugar in a pot of water and bring it to a boil. I’ll get to measurements in a second. When it boils, add your tea and steep. Strain out our tea (or remove the bags), and you’ll have sweet tea. Most people make a very concentrated tea, then add water to it to make the right volume for a batch. This way, you don’t have to boil as much water, and it’s much easier to cool down. Your SCOBY shouldn’t be kept any warmer than 85 degrees, or it will likely die.
Once you’ve got your tea concentrate, you’ll put it in your clean glass container along with enough water to get the right ratios of everything. Then you’ll add your SCOBY and some starter liquid, which would be the finished kombucha. Put the cloth over the top, put the rubber band or string on to hold it in place, and put it in a quiet spot for at least 5 to 7 days.
Where to Keep It?
There are two main things to consider here. One is keeping it out of direct sunlight, and the other is keeping it at the right temperature. Ideally, between 70 and 80 degrees will make your kombucha happy. It takes longer to ferment at the cooler end, and it ferments much more quickly on the warmer end. In the cooler months, I keep an electric seedling mat wrapped loosely around my jar, and that seems to work well. You can get “belts” specifically made for brewing kombucha, and you can get thermometers to stick on the outside of the jar to monitor the temperature, but I’ve never bothered with that.
In the warmest part of the year, there’s an excellent chance that some fruit flies might show up. This is why you’ve got the breathable cloth with a tight enough weave that bugs can’t get in. And fruit flies are annoying, but you can easily trap them in a small dish of vinegar laced with a bit of dish soap. They’re drawn to kombucha just like they’re drawn to the vinegar in the trap.
After you’ve made a few batches, you’ll notice that your SCOBY is multiplying. At this point, you’ll want to keep some of them on hand in their own separate jar, which is commonly called a SCOBY hotel. You’ll want to feed your SCOBY hotel a little sweet tea whenever you make a batch of kombucha, but otherwise it’s just a place for your extra SCOBYs to live. The liquid in there gets extremely tart, and you probably wouldn’t want to drink it. But it does come in handy. I’ll tell you how in just a minute.
The Method I Use
I did a lot of math in the beginning to figure out the amounts of things I use today, and frankly, it’s been so long that I don’t really remember what my thought process was in all that figuring. But it works. I make a gallon-size batch at a time, which yields not quite a gallon of kombucha.
I put 7/8 of a cup of sugar into 3 3/4 cups of water in a saucepan, cover it, and bring it to a boil. When it boils, I add 14 grams of loose tea. I like 7 grams each of green and black. I turn off the heat, recover the pot, and let that sit anywhere from a couple of hours to overnight. And I should mention, that’s overkill, and that’s probably making the tea much more bitter and tannic than it should be, but for me, it’s fine.
I strain the sweet tea into a pitcher and set that aside. Then I gather four quart-size mason jars for the finished kombucha, a ladle, glass measuring cups, and a glass casserole dish for temporarily holding my SCOBY and starter liquid.
I’ll add any flavorings to my mason jars first, usually herbs or a little fruit juice. I’ve been on a hibiscus kick lately, sometimes with a little finely chopped ginger. Then I take my finished batch of kombucha, and the first thing I do is use the ladle to harvest about 3/4 of a cup off the top, which I put into the casserole dish. Then I reach in (with clean hands) and scoop out the SCOBY, adding it to the casserole dish.
I give the kombucha a quick stir with the ladle, then pour it carefully into the prepared mason jars. Then I rinse out the jar a few times (no soap, just water), dry off the outside, and attach a piece of masking tape on which I write the date with a Sharpie. I put the lids on the mason jars and put them in the fridge, then I go on to prepare the next batch of kombucha.
With the concentration of sweet tea I’ve prepared, I need three parts water to one part tea to properly dilute it. So I measure out 3 cups of sweet tea, put that in my prepared glass jar, and add 9 cups of plain filtered water.
Here’s where the SCOBY hotel comes in handy. I harvest about 3/4 a cup of liquid off the top, just like I did with my finished kombucha, and add that to my fresh batch of tea along with the SCOBY and the finished kombucha I reserved in the casserole dish. Then I take the remaining sweet tea (usually about 1/2 cup), add 1 1/2 cups of plain water (keeping that 3:1 ratio), and pour that into the SCOBY hotel. Sometimes there isn’t quite that much room available in the hotel, so I’ll just add the concentrated tea and whatever amount of water will fit. (I’ll also make a mental note that it’s time to clean out the SCOBY hotel, which is a post for another day.)
All in all, here’s the breakdown.
I make a total of 3 1/2 quarts of tea, sweetened with 7/8 cup of sugar, and brewed with 14 grams of tea.
3 quarts of that sweet tea goes into my big glass jar, along with 1 1/2 cups of starter liquid (half from the finished kombucha, half from the SCOBY hotel).
I cover that and let it sit for anywhere from a week to two weeks. I like a very tart, very funky kombucha, so two weeks is fine with me. However, I do enjoy the slightly sweeter, less puckery week-old kombucha too. It really just depends on when I remember to take the 20 minutes to do it.
I know, it sounds like a lot. And there is so much more to brewing kombucha than anyone could possibly cover in one blog post. But if you like kombucha, but you don’t love the price tag (!) or can’t find a flavor that just really this the spot for you, hopefully I’ve demystified it enough that you’ll consider brewing it yourself.
I feel like there’s probably a part two of this post coming as well, so stay tuned.
