I recently drove cross-country for a summer vacation and was asked to teach an intro class to kombucha for beginners at my hometown library. I’ve been brewing kombucha on and off for a few years, and am certainly no expert, but of course I said sure! And then started thinking about the logistics of transporting the needed bits and bobs. It was a bit of a gong show, but ultimately worked out nicely, and now there are twelve new brewers enjoying this delicious drink.
In getting ready to teach the kombucha for beginners class though, I found myself doing some reading and research and have put it all together here. I was surprised to learn of the mysterious and undocumented history of this drink.
Kombucha is a living food with an uncertain history and lineage. Evidence exists of its presence in China and elsewhere in Asia, throughout Russia and Europe. It was popular in Europe and Russia prior to WWII, and then sugar and tea rationing saw it fall out of favour. It resurged in Italy after the war, and became popular in North America in the 1990s.
Its inability to be patented or controlled makes it a bit of a mystery in terms of provable health or medicinal uses. It tastes good, is known to contain probiotics of varying types and quantities, may aid in digestion, and may make a variety of nutrients and vitamins more bioavailable.
Fermentation is a mysterious, ever-changing thing, and no two batches will be the same. Many regular kombucha drinkers report a detoxifying effect, and a positive impact on digestive issues.
Kombucha contains some caffeine, little sugar (depending on how long you brew it for), and very little alcohol (<0.5%). A batch of kombucha can be finished in as little as 5 days, or as long as 30 or more, depending on your taste preferences and brewing conditions. 7-10 days is average.
The main ingredients of kombucha are water, tea, white sugar (or cane sugar), starter brew (finished kombucha with a low pH), and a SCOBY. A what? Read on.
SCOBY: Symbiotic Culture of Bacteria and Yeast
A magical, mysterious, slightly peculiar thing!
Kombucha – and its SCOBY – is a live culture with a floating, sugar eating machine. Through aerobic fermentation the yeast consumes the nutrient solution (tea + sugar) to produce enzymes that separate sugar into glucose and fructose. Glucose consumption by the yeast then creates alcohol and CO2. The bacteria consume the alcohol, converting it to gluconic and acetic acid (hence the vinegar smell and taste) and other healthy acids, and fructose remains in the brew and accounts for the residual sweet flavour.
A product of bacteria and yeast in the brew, a SCOBY is essentially a woven mat of cellulose. It forms on the top of the liquid and takes the shape of the vessel. A new SCOBY is grown on the surface of every new batch of kombucha, but the SCOBY you started with might float, sink, or move around throughout the fermentation process. Over time SCOBYs will get thicker and thicker, and likely get darker as they take up the colour of the tea.
SCOBYs can be peeled apart and shared with friends, or if large enough, cut in half for sharing. The main SCOBY is called the mother, and every new SCOBY that forms is the baby. If you need a break from brewing you can park your SCOBYs in a SCOBY hotel for long periods of time.
Where do you get a SCOBY? Ask your friends, post on a local “Buy Nothing” group, or order one fresh from a supplier online. It may also be possible to grow one from commercially prepared kombucha.
Ingredients & Tools
- Finished plain kombucha from your last batch (or from a friend if you’re just starting out)
- Lowers the pH
- Introduces starter bacteria and yeasts and innoculates the brew
- Consider bottled (not distilled) if your water supply is heavily chlorinated and/or fluoridated. Sit water out overnight to evaporate chlorine naturally.
- White sugar or cane sugar (not honey, maple syrup, stevia, or any other sweetener or substitute)
- Feeds the yeast and is food for the SCOBY
- Added sugar at the beginning of the batch is eaten by the yeast and the end product is much lower in sugar than the sweet tea on day 1
- Sugar is for the SCOBY, not for you
- Black tea, green tea, white tea, or oolong tea
- If using loose tea use the equivalent measures to one tea bag
- Avoid flavoured teas, particularly those with chemical flavour or oils – save the flavouring for the end for the long term health of the SCOBY
- Use naturally (not chemically) decaffeinated tea if you wish to avoid caffeine
- Glass jar or container is best; no metal. Plastic is okay but may take up flavours of the tea over time
- Aim for jars with straight sides and avoid jars with shoulders. My current favourite is a 1.5L glass canister from Dollarama with a decorative beveled ring that makes a great grip when pouring. It’s $3 and makes the perfect amount of finished brew to fit into a 1L storage bottle (see below).
- Something to withstand pressure if you intend to do a secondary ferment for effervescence (with flavouring or plain). This $3 bottle from IKEA is a great option. Alternately, buy something yummy from the grocery store, drink it, and then repurpose it for kombucha.
- Cover your brewing jar with a clean cloth (and rubber band or screw top metal ring if you have one) to let air in and out, and prevent debris or fruit flies from getting in
- Use a square of clean linen tea towel or old t-shirt with fine weave. Grocery store “cheesecloth” is too open to bother with. A coffee filter will also work.
Misc Other Tools:
- Kettle, measuring cup(s), wooden or plastic stirring utensils, strainer, funnel, bowl or jug.
Depending on who in your household likes kombucha, and how much you drink per day (do start small and increase slowly to see how it sits with you!) you might find you want to brew different sized batches. I’m the only kombucha drinker in my house and so I brew the 1.5 L size (bolded), which is plenty for me to consume a small amount each day for about a week to ten days.
Jar Size (approximately)
|Water||Sugar||Tea Bags||Starter Liquid
1 L / quart
|3 cups||¼ cup||2||
|4 ½ cups||¼ cup + 2 Tbsp||3||
|2 L / ½ gallon||6 cups||½ cup||4||
Have a clean work surface, clean tools, and clean hands. Use a tempered glass measuring cup (your standard Pyrex measuring cup) or mason jar for step 1 – not necessarily your brewing jar if you aren’t sure it can handle having boiling water added directly to it.
- Dissolve sugar in near-boiling water: use about one quarter of the total water amount needed. Add tea and steep for five minutes. Remove tea.
- Top up hot, sweet tea with cold water to reach total amount needed for your brew. Make sure it’s not hot or you’ll kill your SCOBY. Room temperature or cool is fine.
- Transfer to your brewing vessel if needed.
- Add starter liquid (finished, plain kombucha).
- Ensure your liquid level is below any shoulder in the jar.
- Gently set SCOBY on surface of brew, and it’s okay if it sinks. Let it do its thing.
- Cover with square of clean linen or old t-shirt, or a coffee filter. Secure with rubber band or metal ring.
- Find a happy spot away from direct sunlight where the temperature is likely to remain fairly steady between approximately 20°-25°C.
- Sing to it, read it stories or poetry, or tell it jokes. Just kidding. Leave it alone for a week, and then use a wooden or plastic spoon, or a plastic straw, to extract some liquid from below the level of the baby SCOBY that grew on the top of the liquid. Taste it! Do you like it? Great, time to bottle. Still too sweet? Taste again in another couple of days.
When your first batch of kombucha is done (you did it!) it’s time to bottle. If you want to make more kombucha for a new batch you can use the mother and the baby SCOBY in the new batch, or you can give one to a friend. It’s never a bad idea to hold back a few for yourself in a SCOBY hotel in case your batch gets contaminated, which is not that common but it does happen.
If you want to start a new batch (or two) then do that first. You will take your finished kombucha and draw off as much as you need for starter liquid (see proportions above for the size of the jar you’re using).
Take the remaining finished kombucha and filter it if preferred. Lay a piece of clean, linen tea towel in a strainer and pour the kombucha through it into a jug or bowl or large measuring cup.
If you like the taste as is it can simply go into a storage jar or bottle and go in the fridge in an airtight container. If you want to try flavours or for some fizz it needs a secondary ferment, which involves adding a wee bit of sugar back into the finished brew to wake up the yeast and get it going. Remember the by-products include carbon dioxide? That’s the fizz. This time, though, you’ll trap it and retain the CO2.
Use a funnel and transfer to a bottle that can withstand pressure. Add up to 40% fruit juice, or chunks of fruit, or if you just want the fizz and no extra flavour then add 1 tsp of white sugar for new food for the yeast. Leave at least 1” of head space. Cap the bottle and leave it at room temperature for at least two days. Taste it again – do you like it? Yay, you’re done! Put it in the fridge and enjoy. Not quite right? Cap it and taste again in a day or two.
My favourite flavour is ginger, and I add chunks of raw ginger to the brew and let it sit for a few more days. Rarely do I bother with anything else, but a quick internet search will turn up dozens of flavouring ideas.
Store finished kombucha in the fridge. Despite the cold temperature it will continue to slowly ferment so the taste may change over time, and a globby blob of sediment may start to form. Strain it before drinking if it squicks you out.
If you find yourself with excess kombucha try adding it to popsicles, smoothies, or salad dressing. Kombucha that you forgot about will eventually become very vinegary. It may not be drinkable but can be used as a starter liquid, or in place of cider vinegar in recipes (if it’s to your taste).
Once you get the hang of the basic process, have fun with flavours and experiment. Keep one batch of plain, standard kombucha going to ensure a healthy SCOBY, and use a second jar with a baby SCOBY to try new tea combinations or brewing time. At bottling time use the plain as your new starter liquid, and try herb and fruit combos with the extra.