I've always loved experimenting. I had a cheap microscope as a kid and there wasn't much I came across that I didn't try and put under the lens to examine. I guess maybe this is one of the many reasons I'm studying to be a dietitian, there's so much science (and sometimes seemingly alchemy) happening within our food! A week ago today, my friend Sarah gave me a priceless gift, a jar containing two SCOBYs. What's a SCOBY you ask? Well, a symbiotic colony of yeast and bacteria, of course! Up until last week I was more or less clueless about the process that went into making the bottles of expensive fizzy tea I like to drink so much. And to be honest I am still sort of hazy on the whole process.
But, taking into account a bit of what I learned in microbiology last semester, I grasp that the bacteria in the SCOBY ferment the sugar (sucrose) that you add to the tea and break it down into smaller sugars (glucose and fructose) while also producing acetic acid (as in vinegar, which you will likely detect upon first taste) while the yeast in the SCOBY "eat" the broken down sugars and produce alcohol (yep, kombucha is slightly alcoholic, about 1% depending on fermentation time) and carbon dioxide (yay bubbles!).
So how does it work? Incredibly easily, even for someone like me who is less-than-great at following precise instructions. Once I got the prized SCOBYs safely home, I brewed some black tea with sugar, let it cool, poured it into two large jars, plopped in the SCOBYs, and covered the jars with rubberband-ed coffee filters. I then let the brew sit in my dark pantry for a week, excitedly peeking in on it about 10 times a day. And wah lah! Upon tasting the finished product this afternoon, I deemed my kombucha brewing endeavor a success.
After 7-10 days of fermentation, the kombucha can be further carbonated by being placed at room temperature in a sealed container. Once it's bubbly to your liking, you can get creative by adding all sorts of add-ins like fruit or herbal teas for nuanced flavors (at this point you'd want to refrigerate your 'bucha.)
This round, I bottled a jar of plain, a jar of ginger (using ginger tea) and a jar of Tazo passion tea (another great suggestion from Sarah).
Below I'll post the recipe Sarah shared with me. I am super grateful to her for the SCOBYs and for helpful tips along the way. What an awesome way to get in on the DIY movement that's bubbling up from the underground these days.
In terms of obtaining a SCOBY, starting chumming it up with a generous friend who you know brews kombucha, otherwise this SCOBY on Amazon has very good reviews.
For a 1/2 gallon jar:
7 tablespoons sugar
2 1/2 teaspoons (roughly) black tea (I used 3 tea bags)
1-2 cups starter tea (if you are starting a new batch, two more cups of water)
Or for a gallon jar:
3 1/2 quarts (14 cups) water
1 cup sugar
2 tablespoons tea (~6 tea bags)
2 cups starter tea
Boil the water.
To a sterile (or at least very clean) 1/2 or full gallon glass jar, add sugar and tea bag(s). Pour in the piping hot water and and steep until tea is at room temperature.
From Sarah, "I have read that it is best not to use metal pots [for steeping the tea]... Also, don't fill the [brewing] jars too high, keep the liquid below where it starts to taper in at the top. If the tea level is too high the SCOBY will grow up and cling to the glass too much, ending up out of the tea.
"Cover jars tightly with a breathable barrier (cloth or paper filter). Keep at room temperature. Once tea is finished you can pour into a container and keep in the fridge. I think I read that letting it sit at room temp while capped will create more carbonation, but I'm not sure (it may explode at some point!). I like to flavor mine with herbal tea once it's finished. I add 1 tea bag per finished batch (from one 1/2 gallon jar). There are tons of other ways to flavor too.
...I usually "rinse" out clean jars with white vinegar before starting to brew in them. There is also a method for tasting for doneness - use a very clean straw, slip along side of the SCOBY, then cap straw top with your finger to pull up some tea and drop it into your mouth. Although I usually just stick a spoon in there! Or lately I haven't even be tasting, I can just tell by the smell of it now!"