Kombucha 101 October 30, 2014 14:21 2 Comments

Are you tired of paying $3.99 a bottle to get your kombucha fix?  Is the effervescent goodness of billions of beneficial bacteria really worth the cost?  Or, are you just paying for a plastic bottle and pretty label?

Brewing your own kombucha is super easy and can save you a lot of money... not to mention guilt over the disposable packaging.  Kombucha is loaded with beneficial microbes that help support gut health and these probiotic cultures are especially active in homemade kombucha because it isn't heat-treated and it doesn't sit around waiting for you to buy it.  When you make it yourself, you can have it fresh and just to your liking: use whatever tea you like best; control how tart it gets by limiting the amount of time it ferments; you can even throw in fresh fruits for flavor.  Every brew is a new possibility!

First, what is fermentation, besides being all the rage recently?  Fermentation is the metabolic process of micro-organisms that convert the sugars found in fresh foods into the acids that lend fermented food products their characteristic tanginess.  Far from simply letting food rot, it is actually a very controlled and safe process.  Many of mankind's oldest and most revered foods are actually the products of fermentation: yogurt, cheese, bread, and beer just to name a few.  Kombucha is purported to be at least 2000 years old, probably originating under conditions far less sanitary than today, although basic food safety protocol should be followed any time you're preparing foods for fermentation at home.  That means diligent hand-washing, washing all utensils thoroughly, and no double-dipping when you go to taste the products of your fermentation experiments!
A live SCOBY is thick and gelatinous. 
A live SCOBY is a thick and gelatinous thing.
The most important ingredient for making kombucha is the SCOBY--Symbiotic Culture Of Bacteria and Yeasts--that's what turns ordinary sweetened tea into the fizzy, tart beverage we call kombucha.  Many people get their first SCOBY from a friend or aquaintance who is already making their own kombucha.  At Homesteader's Emporium, we're propagating and selling fresh, live baby SCOBY's!  Fresh is best, but if you're travelling far or, for whatever reason, not going to use your new SCOBY right away, you can get dried, dormant SCOBYs.
You may be able to start making your own kombucha using equipment that you already have in your kitchen.  You'll want a non-reactive (i.e. not metal, unless it's stainless steel) container in which to let the tea ferment and a cover for this container that is tightly woven to keep fruit flies out, but not airtight.  If you don't already have something that fits the bill, Homesteader's Emporium has you covered: we sell fresh SCOBYs with starter tea, a 1 gallon glass jar, elastic jar cover, and pH test strips (to monitor the acidity of your brew).  You'll also need tea bags (or loose leaf tea), granulated white sugar, a pot with a lid, a funnel, and a plastic or wooden spoon.  Most people brew in 1 gallon batches and most recipes are written for a batch of this size, but if you're using a 1/2 gallon (or 2l.) pitcher or jar, you can divide recipe ingredients in half (it's not necessary to divide the SCOBY in half unless you're doing two separate batches at once).
Getting started is as simple as making tea.  You can use almost any tea, as long as it's caffeinated and doesn't contain essential oils (as in Earl Grey).  Black tea is traditional and creates a bold, full-bodied kombucha.  Green tea can be used to make a refreshingly light kombucha.  Herbal teas may be used every once in a while or can be used for flavoring in combination with a few black or green tea bags.  But, bear in mind that the SCOBY micro-organisms have evolved in the presence of caffeine so making back-to-back batches of caffeine-free kombucha can lead to a deterioration of the SCOBY, as it won't get all the nutrients it needs.
A cotton steeping bag would've been handy to use with my loose leaf tea.  Instead, I'll have to strain it.
A cotton steeping bag would've been handy to use with my loose leaf tea. Instead, I'll have to strain it.
Make the tea in a large stockpot.  For a 1-gallon batch of kombucha, bring 3 1/2 qts. water to a boil.  Use 8 single-serving tea bags (or 2 tablespoons loose leaf tea).  While the tea is still hot, stir in 1 cup of granulated white sugar until it dissolves (don't worry--it won't contain all that sugar in the end).  Cover the pot and let the sweetened tea cool down to room temperature.  If you make the tea in the evening, it will cool overnight and be ready to use the next morning.  If you want to cool it faster, place the pot of tea in a large bowl of ice water and stir until it cools.
Testing pH before fermentation.
Testing pH before fermentation.
When the tea is cool, pour it into the 1-gallon glass jar.  Top up the jar with the starter kombucha that came with your SCOBY.  The starter has already undergone fermentation and is, therefore, quite acidic.  Adding it to the new batch of tea will acidify the tea, creating an environment that is inhospitable to foreign contaminants.  If you have pH test strips, it's a good idea to test the tea before it ferments.  With the addition of the starter tea, the pH should be around 4.6 or lower.  If it's not, add the juice of 1/2 a lemon and test again.  In the future, before you start a new batch, remember to save 2 cups from your last batch to use as starter tea. With the new batch of tea sufficiently acidic, it's time to add your SCOBY.  Gently slide it into the jar of prepared tea; whether it floats or settles on its side doesn't really matter.  As the tea ferments into kombucha, a new SCOBY layer will form on the surface of the tea, assuming the shape of whatever vessel it's in.  Here, I've covered the jar with a double layer of cheesecloth held in place with a rubber band.  This will allow the SCOBY to breathe, but will keep out fruit flies.
Cover the jar of tea with a tightly-woven, but not airtight, jar cover or cheesecloth held in place with a rubber band.  Label the jar with the production date or mark it on your calendar and let it sit at room temperature for about a week.  It really can be considered done from 5 to 14 days after production, by which time the pH of the kombucha will decrease to around 3.0.  You can test it again with a pH test strip to monitor the process, but the real benefit of making your own kombucha is the freedom to decide when it's done based on personal taste.
During the fermentation period, the SCOBY micro-organisms consume the added sugar and produce lactic and acetic acids, causing the kombucha to become increasingly sour.  If you like it rather mild, you may taste it after 5 or 7 days and decide it's perfect; if you like a really sour punch in the mouth, let it ferment for 10 to 14 days.  Any longer than that and it may get so sour it tastes like vinegar--but maybe that's how you like it!  Don't worry if this happens and you can't drink it, the SCOBY will be fine; just toss most of it, reserving some to use as starter tea for a new batch.  Your kombucha is done when you say it's done.  At that point, move it to the refrigerator and enjoy!
Or, you may want to experiment with carbonating your homemade kombucha.  I, for one, prefer my green tea kombucha to be lightly effervescent: served over ice, it makes a refreshing summer bevvie.  Carbonation is simply carbon dioxide dissolved into a liquid under pressure, which escapes in the form of bubbles when pressure is released.  Carbon dioxide is created throughout the fermenation process, as a by-product of the metabolic activity of microbes consuming sugars.  So far in making your kombucha, it's fermented in a container with a breathable cover, so the CO2 has been able to escape.  When the flavor is to your liking, you can drink it--it'll be flat--or you can transfer it to airtight bottles that will trap CO2 as it continues to be created.
Swing-top bottles (like the ones Grolsch beer comes in) are ideal for this because they're airtight and reusable without requiring bottle-capping equipment.  You can find used ones in recycling bins around the city; if that grosses you out, Homesteader's Emporium sells new swing-top bottles in various sizes.  Alternatively, you can use plastic soda bottles; it's easy to tell when pressure builds inside of these because they'll feel hard when you try to squeeze them, but they're also more prone to bursting under pressure if you don't move them to refrigeration promptly after they get hard.  Whatever bottles you use, fill them with kombucha, using a funnel, but leave a headspace of about 5 cm.  Remember to reserve some starter tea for your next batch!  Close the bottles and leave them at room temperature for another 2-3 days, during which time the pressure will build inside the bottle and force CO2 to be dissolved into the kombucha.  After this secondary stage of fermentation, transfer the bottles to the refrigerator and enjoy!
Swing-top bottles for carbonating your kombucha.
Swing-top bottles are perfect for carbonating your kombucha.
At whatever point you decide to put your bottles into the refrigerator--carbonated or not--the fermentation process will slow waaaaay down and the flavor will not change noticeably in the time it takes you to drink it.  That being said, fermentation does continue, albeit very slowly, at low temperatures and many people believe that the additional flavor components created during a months-long, low-temperature fermentation are subtle, but more complex than those created in a faster, warmer ferment.  In my experience, this is entirely true.  I once discovered a bottle of homemade kombucha hiding in the back of my refrigerator that must have been there for six months or more.  I opened it with trepidation, believing that possibly it had gone bad and would be undrinkable; imagine my surprise when it turned out to be the best kombucha I've ever had!  Alas, I have not repeated that particular success because I don't have the patience to put my kombuchas away and forget about them for months at a time.  If you have the space and the patience, go for it!
If you were hoping for a sure-fire recipe for the perfect kombucha, to follow to the letter, I hope you won't be deterred by my loose recommendations on timing.  (Our easy-to-follow, beginner-friendly primer on brewing kombucha can be found here.)  Aside from personal preference, environmental factors like heat and humidity play a role in the development of fermented products and these things are hard to control outside of a factory.  Don't expect your first batch to taste just like a $4 bottle of GT's and don't expect your brews to be consistent, at least not in the beginning.  Even when you follow the same recipe, your kombucha may be a little different from one batch to the next and that's okay.  Don't be afraid to experiment and don't be afraid to fail--only through experimentation will you truly begin to understand and appreciate the depth and breadth of fermented goodness.