Their most popular function is to stimulate fermentation in a sweetened tea. Basically, after insertion into the tea, the culture will consume the sugar and produce magical healthy stuff throughout the fermentation. After one to three weeks, depending on various factors, the result is a delicious (at least I think so; it tastes rather like Miruvor) drink that people on the internet claim can cure or prevent cancer, alzheimers, zombie apocalypses, sore throats, the Black Breath, and generally whatever we can think of. In reality, there have apparently not been any seriously professional studies into its health benefits, but users tend to attribute much credit to the general health benefits of "kombucha tea." I have no way of knowing how much of it is true, but personally, it did seem to help with a cold I had a couple weeks ago. And if live bacterial cultures aren't good for us, how come they are always advertised as being added into our yogurt?
Once the desired balance between bitterness and sweetness is achieved (you might taste the drink every day after a week until you find the quality you like) the cultures (which usually look like little slimy pancakes) can be removed and the drink even flavored further with fruit. An example of pineapple flavoring in my refrigerator:
Green tea is the most popular choice, but you can use just about anything. Here is a picture of a few of my fermentation jars (coffee filters on top so the cultures can breath) including black cherry tea, peppermint tea, black tea, green tea, and some other random teas that were Chinese so I couldn't read the labels.
Yes, the drink is slightly alcoholic due to the fermentation, but it is usually only 0.5%, which is one tenth of the normal alcohol concentration of beer, and not nearly enough to be legally recognized as an alcoholic beverage. You couldn't get drunk on it if you tried.
If it ferments for more than three weeks, it will become "kombucha vinegar," which can be used for all the normal applications of more common vinegars, probably to greater effect in many cases. Most popularly it is used in vinaigrettes, or as a natural hair tonic/shampoo/conditioner substitute.
The maple leaf shaped container is where I keep my vinegarized kombucha. I use it in my hair, and it's great. Also pictured is a larger jar going into deep fermentation for replenishment of my vinegar. The two cloth-covered containers are for the growing of particularly large cultures for use in seamless constructions. Scroll up and notice how all of my fermenting drinks have a slimy pancake floating on the surface as well as one sitting on the bottom. The cultures reproduce during every fermentation, growing a new culture to fit the shape of the container's surface. My circular container is currently growing a culture which I hope to make into a sort of drumhead thing. The rectangular container is growing one which will be made into a pouch.
The cultures dry out into a leatherlike consistency. If a pattern is cut out and assembled over a mould, it will effectively stitch itself together as it dries. I came across this idea from a woman named Suzanne Egg who is a fashion designer and makes clothing out of this stuff.
The other day I cut out a pattern for a pouch thing from the bacteria in my rectangular vat, pinned it around a box shaped mould, and hung it to dry in front of my window. It will require some patchwork and other additions after it dries, but it will eventually be a functional piece of equipment.
After this first project is complete I am planning to try growing a pair of shoes.
If any of you are interested in experimenting with this, just PM me your address, and I would be delighted to mail you a culture and provide you with further instructions on how to safely make use of it.
