SCOBY DOO – Kombucha

It’s official! I’m a kombucha fan. I drink it in small amounts as a medicinal. It makes my gut feel good and it is delicious!

There are lots of purported health benefits from drinking kombucha (improved digestion, reduced blood pressure, arthritis relief, increased immune response, cancer treatment), but no clinical trials confirming them. There are loads of interesting scientific papers about kombucha and its components and effects (anti-microbial, hypoglycemic, renal repairing, probiotic), but a clinical trial is a very specific type of study involving human subjects. Clinical studies are  expensive and it’s difficult to get approval to perform them (that’s why mice are so popular).

I ain’t afraid of no lack of clinical studies! In real life, we just need to make our own decisions based on the information at hand. Thanks to Sandor Ellix Katz and The Human Microbiome Project, I am entirely sold on the idea that a variety of fermented foods in our diets is essential for a robust gut flora, and that a robust gut flora improves the function and well-being of our entire body (including our mind). Lacto-fermented vegetables, yoghurt, kombucha, kefir, sourdough…it’s all good in my opinion. “A little bit of everything”, is my motto.

What is Kombucha?

Kombucha is a fermented drink, made by feeding a sweet tea to a kombucha SCOBY (symbiotic community/colony/culture of bacteria and yeast). The resulting beverage is a slightly carbonated, acidic beverage comprised of sugars, organic acids (like butyric acid which is an important anti-inflammatory), vitamins, and minerals (this is a nice detailed analysis). It will contain vinegar, vitamin B, traces of the kombucha SCOBY, and whatever constituents the original tea had (caffeine, polyphenols, volatile oils, etc). As vinegar is produced by acetic acid bacteria (in this case Acetobacter xylinum) feeding on ethanol (that’s regular old alcohol) in the presence of oxygen (open jar), there can also be tiny traces of alcohol.

Kombucha has been around for thousands of years, and has long been used by traditional cultures to improve digestion, boost immunity, eliminate kidney stones, reduce high blood pressure, and create sustained and lasting energy.

The kombucha SCOBY is distinct from the kefir culture, tibicos, and other SCOBYs, meaning it is made up of different constituent microorganisms. The kombucha SCOBY is a very distinctive mass of white cellulose which grows on the surface of each new batch of tea, forming layers that fuse together. It looks kind of like a jellyfish. It evolved feeding on tea and I use green tea for mine. You can use herbal tea, but it will mature more slowly. It is happiest chowing down on tea made from tea tea (Camellia sinensis).

My Green Tea & Chamomile Kombucha

My Green Tea & Chamomile Kombucha

I Want Some!

You can buy ready-made kombucha drinks at the grocery store. There seem to be new brands popping up all the time. If you do buy one, I recommend looking for one that says what kind of tea they used not just the flavours they added. It’s an important piece of information so it should be on the bottle.

If you want to add a friendly kombucha critter to your household you can get your own kombucha SCOBY. They can be purchased locally in Vancouver from Grass Roots Greens and Homesteader’s Emporium. They are easy to care for and hard to kill (I find kefir a bit too demanding).

The best way to get a kombucha SCOBY is to get one from a friend. They grow, and grow, so anyone who has one will have plenty to give away. Ask around. I’ve seen postings on Village Vancouver and Craigslist. All they have to do is peel off a layer for you and give you some mature liquid for your first batch. (see full instructions below)

If you’re patient, you can even grow one from store-bought kombucha. It can take a few weeks, but it works. I found this video online showing how to make it from Original GT’s brand kombucha. Pretty cool!

Is it Safe?

Due to its acetic acid content it is inherently safe and protected from contamination by pathogens. That is the case with all fermented foods since the point of fermenting is usually preservation. You’re creating an environment that supports the desired bacteria and prevents the undesirable. You don’t need laboratory level sanitation at home to feel okay about making kombucha or other fermented foods. Just normal sanitation. Contamination of the SCOBY is possible and will appear as colourful mold, but it’s very rare especially if you provide enough sugar and starter (mature acidic kombucha) to each batch. The Culture For Health Kombucha FAQ has lots of excellent detail and they sell kombucha SCOBYs so they know their stuff.

Kombucha is an acidic drink. Yep. That means acid, yo! Your body does not expect you to chug a litre of acid, so don’t. It’s not a toughness contest! I like my kombucha when it’s got a bit of tang, but still wonderfully drinkable, and yet I still only drink 1/2 -1 cup at a time. You will upset your stomach if you over do it and fanatics have caused themselves serious damage (acidosis) by drinking massive amounts of kombucha. Imagine chugging an entire 4 litre jug of vinegar every few days and you get the idea. Ca-razy. So, just don’t be crazy. Okay? Remember: the more vinegary it tastes, the more acidic it is so just gauge for yourself what feels drinkable and dilute as necessary.

Urban Huntress Tip: Consider kombucha a delightful medicinal beverage. It’s not a replacement for water!

Rx Caution: Changing the acid level in your stomach can change the bio-availability of some medications. Don’t take both at the same time and check with your pharmacist or doctor if you take life-changing pharmaceuticals. Just so you know.

SCOBY DO’s & SCOBY DON’Ts

Caring for your Symbiotic Community of Bacteria and Yeasts

To get started you will need:

  1. your kombucha SCOBY mother in some mature kombucha (starter),
  2. a big glass jar,
  3. a breathable cover for the top of the jar (coffee filter, thick cheese cloth or other cloth to keep out bugs and dust),
  4. an elastic band to secure the cover,
  5. sugar (actual sugar, not stevia/xylitol/maltitol, is required). Organic or white sugar – I don’t recommend using coconut sugar because it tasted weird and I avoid using strong flavoured sugars as it can overtake the flavours I like. Experiment for yourself, as far as flavours go. Molasses (which makes natural sugar brown) is good for you since it’s an excellent source of magnesium.
  6. tea (black, green or white – preferably organic).

General Guidelines:

  • Whatever size jar you have to use, you always need at least 10% of the liquid for each fresh batch to be from a previous mature batch. It needs a slightly acid environment.
  • If you don’t have enough mature kombucha (like for the first batch) you can supplement with some vinegar diluted with 2 parts water.
  • Kombucha SCOBY needs air and room temperatures. Keep it in a jar with a cloth or cheesecloth secured over the opening (to keep out dust and critters) and leave it on the counter.
  • If transporting the kombucha mother, don’t keep it sealed in glass for more than a few hours. It produces a lot of carbon dioxide, so you need to release the pressure regularly.
  • If you want to do an experimental batch, remove some kombucha SCOBY and do the batch in a separate jar. You don’t want to risk killing your entire SCOBY.
  • Some herbs have anti-fungal and anti-bacterial actions (e.g., sage, oregano, thyme, rosemary) so use them with caution and do it in a separate jar.
  • Unpasteurized honey has anti-bacterial properties, and has been known to kill kombucha SCOBYs. If you are determined to use honey as your glucose source, it must be pasteurized which you can do yourself at home.
  • The kombucha SCOBY is happy to just sit in its starter liquid for quite a long time (up to 6 weeks on a full size batch), so don’t worry if you don’t get around to feeding it for a few days.

Making a fresh batch of kombucha:

  • You need to make some tea!
  • I use 2 bags of organic green tea. Some people use more. You can also use black tea, white tea or herbal tea.
  • ½ cup of sugar (actual sugar)
  • I add 2 Tablespoons of chamomile flowers in a tea ball or bag. You can add any herbal tea of choice for additional flavour or make it plain and add it to juice or cooled herbal tea when you drink it.
  • Put tea and sugar in a 4 cup measuring jug, add boiling water and stir until sugar is dissolved.
  • Let steep until room temperature.
  • If you’re in a hurry, steep the tea for 30 mins in 1/3 less boiling water so you can add cool water to bring the temperature down faster.  Use previously boiled or filtered water if possible (chlorine in tap water could affect your SCOBY).
  • I add another half cup of cooled water from the kettle to top it up the tea a bit, so it fills my jar.
  • Add the cooled sweet tea to the jar, pouring gently over the kombucha mother and 10% kombucha liquid.
  • Cover and leave on your counter for a few days.
  • Taste it after 3 days. I like it around day 5-7 as my kombucha seems to work on turbo. Taste it every couple of days until you like it, then decant most of it into a plastic bottle and keep in the fridge. Sealing it and putting it in the fridge will prevent it from getting more sour (acetobacter needs oxygen). Remember: leave some mature acidic liquid (10% minimum) in the jar.
  • Feed the SCOBY with a fresh batch of tea.
  • Contamination Note: I don’t remove my SCOBY from its jar each time as I prefer to avoid opportunities for contamination. I just pour off the mature kombucha and add fresh tea to the same jar. I remove the SCOBY about once a month to clean the jar.

Storage Note: I recommend keeping mature decanted kombucha in a plastic bottle so the pressure can’t build up too much. With a glass container you need to release the pressure every couple of days, although, that’s not a problem if you’re drinking it every day. I know too many people who have had kombucha all over themselves and their ceilings to bother fussing around with a glass bottle. It’s not worth it to me. If you do keep it in a glass bottle you will get a higher level of carbonation (more bubbles)….but you also might end up with it all over the kitchen. Your call.

My Kombucha is too sour!

Don’t despair. You made vinegar. Quick, easy, flavourful and natural vinegar. Yum! Use it in salad dressings, soup, sauces, or just store it in the fridge to use as your mature liquid for future batches of kombucha – this is especially handy if you made a super delicious batch and you don’t want to leave any in the jar. I have a bottle designated as the vinegar kombucha bottle, so I don’t get it mixed up with the drinkable batch. You can still drink it if it’s really sour, just dilute it with water or juice so it tastes better. Keep in mind that even if you think you’re all hardcore like and can drink super-sour kombucha straight up, you’ re drinking something very acidic and your stomach will not thank you. Just dilute it you big lug.

I have too much Kombucha SCOBY!

Cool. Give some away. You can even eat it (the kid in this video thinks it’s awesome). Some people make candies out of it and others blend it up and use it as a skin cream. There’s even a picture of a motorcycle jacket made out of it (dried cellulose) in Sandor Katz’s book The Art of Fermentation! If you’re at a loss, compost it – I’m sure the soil will thank you.

I have more kombucha than I can drink!

There are lots of different ways you can use kombucha. I think it’s fabulous in soup or stock. I have used it in place of wine, vinegar and stock in recipes. I also add it to pasta sauce and the cooking liquid for grains and lentils. Use it in any recipe that calls for apple cider or wine vinegar like salad dressings and marinades – this is a perfect use for batches that are too sour for regular drinking. It can be used in cocktails or mocktails. You can even make kombucha popsicles (on its own or mixed with fruit or juice) which is a wicked idea especially if you have too much kombucha on hand!

I need a kombucha break!

If you are going away or just want a break from the kombucha cycle, the SCOBY can survive for up to 6 weeks on one batch of sweet tea. So feed it and leave it in its usual cool dark corner. Use the resulting kombucha as vinegar – the acidic content will be high enough that you can just store it in a clean glass bottle in the cupboard.

After 6 weeks, the kombucha can begin to struggle to survive without fresh food. If you don’t want it to die, you will need to feed it again. It is possible to put it in the fridge and put it into hibernation, but many people have had difficulty getting their SCOBY to spring back afterwards, so it’s a risk. Cool temperatures will slow it down, but a fridge is a bit too cold.

I heard there’s no sugar or caffeine left in mature Kombucha!

I’ve heard this too. But anyone who drinks kombucha will know that it still tastes slightly sweet. From what I’ve read, the kombucha will consume the glucose and sucrose (as much as it can), but the fructose is hardly consumed at all. As far as the caffeine goes, I did find a scientific paper that shows some of the caffeine is consumed by the kombucha. So, the fermentation process will indeed reduce the caffeine level.

Further Inspiration

The Cultured Pickle Shop in Berkeley, California is always posting beautiful pictures of their SCOBYs and creatively flavoured kombucha. According to Sandor Katz, they make their kombucha in big batches with green tea and then do secondary ferments with the flavours. They make so many amazing things at this shop!

Sandor Ellix Katz has two wonderful books about fermented foods, Wild Fermentation and The Art of Fermentation. I discuss his books in my post Sandorkraut in da house! and his super simple fermented veggies/sauerkraut technique in the post Fermentation Workshop at UBC Farm. He is a lovely, lovely human.

The website Cultured For Health has loads of well-presented information.

Recommended Reading on The Human Microbiome Project & related research: