As our pepper fermentation expert says above, a lot of this...
I first made kombucha out of frugality. I was a student at the time and making $8 an hour on a goat farm. Fancy lacto-fermented beverages simply weren't in my budget. I scoured Craigslist for a kombucha mother (which now seems somewhat sketchy, I'll admit) and started making my own.
In those days, I felt like I was part of some food counter-culture. I made kombucha and mead, sauerkraut and kimchi, yogurt and kefir. I knew about Sandor Katz long before he won a James Beard, and I clung to my stained and bedraggled copy of Wild Fermentation like some kind of sacred oracle.
I haven't stopped doing any of those things, but I view them in a different light. I think you can make the argument that cooking and making traditional foods can be political acts, and there is a part of me that identifies with this way of thinking. However, it would be dishonest to say that this is why I do what I do. I do what I do because I enjoy it. It makes me happy. How terribly mundane of me.
For those of you new to kombucha or fermentation in general, let me say that it is unlike any other means of turning raw ingredients into food. In cooking and baking, the process is linear--you prepare your ingredients, cook them, then consume the result.
Fermentation is always somewhat unpredictable. It is cagey. It is the opposite of microwave cooking. You end up feeling more like a spectator than a cook. Essentially, you prepare an environment that certain microorganisms will like, and then hope they show up.
The process brings up a lot of questions. For instance, the blog we posted about fermented Louisiana-style hot sauce two years ago easily has the most comments of any other post on the site. Most of the comments are questions.
Kombucha is a little more straightforward. Rather than waiting for lactic acid bacteria to come along, you actually introduce the microorganisms you want into the substance via a SCOBY.
Many people refer to the somewhat slimy, flesh-colored object at the top of a container of kombucha as a "mushroom" or a "mother." Either of those terms work colloquially, but the most accurate way to describe what's going on is to call it a SCOBY. SCOBY stands for "symbiotic community of bacteria and yeast."
I have to warn you--some people find the SCOBY to be utterly repulsive. John loves to drink my homemade kombucha, but he gets grossed out by the sight of the SCOBY. Other people won't drink kombucha at all, not because they don't like the flavor, but because there was this slimy, jellyfish-like creature in it at one time. It doesn't bother me at all. You've been warned.
Finding a SCOBY
The process of making kombucha is actually very simple. In my opinion, the hardest part is finding a kombucha SCOBY, and even that isn't very hard. The best way to get a SCOBY is to find someone you know who makes kombucha. They will be happy to help.
You see, every time you make a new batch of kombucha, the SCOBY reproduces. So at the end of the process, you have the old SCOBY (which is usually still viable) and the new SCOBY. You only need one for a batch of kombucha, so when you're on the hunt for a kombucha mother to get started, folks tend to be very generous.
You can also buy a kombucha mother. There are dozens of sources online, and depending on where you live you might be able to find one at a health food store.
Finally, you can grow your own mother. Simply buy a bottle of unpasteurized (it must be raw for this to work), unflavored kombucha. Pour it into a wide-mouth jar and cover the jar with a scrap of kitchen towel or other thin fabric. Secure the fabric with a rubber band to prevent flies or dust from getting in. Keep the jar at room temperature. Over time, a thin, gelatinous membrane will form at the top of the jar--this is a SCOBY. This may take up to two weeks or longer depending on temperature and weather.
Once your SCOBY has formed, make smaller batches of kombucha at first. Gradually, the SCOBY will get thicker, and you can make larger batches.
The Process In A Nutshell
Once you have a SCOBY and some "starter tea" (raw, fermented kombucha from a previous batch), making kombucha is easy. Simply brew black tea with sugar, let it cool completely, add the SCOBY, cover, and wait. Taste the tea throughout the process--it will become more acidic and less sweet over time, so stop fermentation when you like the way it tastes.
You can proceed with an optional secondary fermentation if you like. This will add some carbonation to your finished kombucha. Simply decant the kombucha into jars and seal (you can use glass jars or plastic bottles). If your kombucha is quite sour, you may want to add a teaspoon of sugar to each jar to jumpstart secondary fermentation. I have also had great luck with adding whole berries to each jar. The yeast present on the surface of many berries is enough to make kombucha effervescent.
There is a lot of speculation surrounding kombucha. Namely, that it is "healthy" and can cure or help treat disease. I remain skeptical as to whether this is even remotely true. I drink kombucha because I like it and because getting some extra probiotics can't hurt. We are not, in any way, promoting kombucha as a substance that can treat or cure disease.
There has also been some concern over kombucha's alcohol content. Most kombucha is very slightly alcoholic--usually less than 0.5%. However, this varies. I have never consumed kombucha that was alcoholic enough to cause any side effects, but it's something to be aware of.
Finally, how do you know when your kombucha mother is no longer viable or is bad? Kombucha smells acidic, vinegary, and fruity (sometimes like strong apple cider). It should never smell putrid or rotten. If it smells very bad, throw it out. Kombucha mothers vary widely in appearance. They may appear cream-colored, light brown, flesh-colored, or any variation on those colors. They may be mottled or develop holes. They usually have brownish yeast strands hanging off them. All these things are fine. However, if your kombucha mother develops mold of any kind, throw it, and the batch of kombucha, away.
Kombucha Dos and Don'ts
DON'T use a metal vessel to make kombucha--over time, the acidity of the kombucha can corrode the metal, give off-flavors to your kombucha, and even kill your SCOBY.
DO use sugar to ferment your kombucha. Sugar substitutes will not work. Honey might work, but over time it may weaken your SCOBY or kill it (there are SCOBYs you can buy that work specifically with green tea and honey--this is called jun rather than kombucha).
DON'T use flavored teas. Black, green, white, oolong, and pu erh teas can be used to make kombucha. Herbal teas can be used, but over time they can cause the kombucha to weaken. If you use herbal teas, use them in conjunction with another type of tea. Stay away from flavored teas (Earl Grey, for instance)--the oils in them can inhibit fermentation and weaken your SCOBY.
DO experiment with different flavors. After the primary fermentation, you can remove the SCOBY and a cup or so of tea for the next batch. Then, add your flavorings to the rest of the kombucha. You can use chunks of fruit or berries, ginger, citrus (zest and/or juice), spices, herbs, hibiscus flowers, etc. Let this sit for a few days or until the taste is to your liking. Then, bottle the kombucha for secondary fermentation. Alternatively, you can bottle the finished kombucha and add fruit juice directly to the bottle.
This is a lot of information to process at once, but I wanted to cover all the bases. Kombucha is very easy to make once you know the process. Below is a simplified recipe to get you started.
Bring to a boil:
4 cups (1 quart) water (preferably not chlorinated)
Remove from the heat and add:
8 tea bags or 2 tablespoons loose tea (black, green, white, oolong, or pu erh)
1 cup sugar
Stir to dissolve the sugar and allow the tea to steep for 15 to 20 minutes. Remove the tea bags or strain out the loose tea and add:
12 cups (3 quarts) cold water
Pour the cooled tea mixture into a large jar or vessel of some kind (not metal) and add:
1 mature kombucha SCOBY and 1 cup "starter tea" (fully fermented kombucha from a previous batch)
The SCOBY may float or sink--both are normal. Cover the jar with a cloth or paper towel secured with a rubber band.
Ferment until the kombucha is as sour as you want it. This will take longer in the winter than in the summer. My most recent batch took 10 days.
Taste it periodically.
When the kombucha is done to your liking, remove the SCOBY (and the new SCOBY that has formed on the surface of the kombucha) and 1 cup of starter tea for your next batch. You may drink the kombucha right away or proceed with a secondary fermentation.
For secondary fermentation, decant the kombucha into bottles and seal. If your kombucha is already very sour, add a teaspoon of sugar to each bottle to jump start fermentation. You may also add a few berries to each jar. Let the bottles sit at room temperature for a few days. At first, you may want to use plastic bottles with screw-top lids--when the bottles feel tight, the kombucha has fermented enough and can be refrigerated.