What’s the fuzz with Kombucha?

You’ve probably heard of it before, and if you haven’t, you’re about to!

Kombucha is a new drink phenomenon that is sweeping the world. It is most common in trendy cafes but has now found its way into supermarket fridges. But perhaps more excitingly, it can be made at home! And with titles such as a cure-all health tonic, who wouldn’t want to make it in their own kitchen?

First of all, what is it? Kombucha is a fermented tea. It is made by preparing black or green tea, sweetening it and then adding microbes. These microbes come in the form of a SCOBY, which stands for Symbiotic Culture Of Bacteria and Yeast. Also more scientifically called a pellicle or more informally called a mother (lending itself to countless puns). It is a sort of gooey mixture of microbes in a cellulose network, it looks a bit foul. And, as you can imagine, there’s a whole lot of science mixed in there too!


Kombucha in its purest form, home-brewed. Showing the white scoby floating on top of the liquid kombucha, the part you drink. Image courtesy of JP

The process involves several chemical reaction. The first is the fermentation of sugar into alcohol, this is facilitated by the yeast in the scoby. Unlike other fermented drinks like wine or beer, the alcohol does not persist. It goes through another step facilitated by the bacteria. The bacteria turns the alcohol into acetic acid, which is vinegar. And after 8 to 30 days of brewing, the Kombucha is finished, there is no sugar or alcohol left, it is all vinegar. The scoby is then skimmed off the top and it can be drunk on its own or mixed with other drinks, like fruit smoothies.


A simplified illustration of the complex chemical pathways in Kombucha brewing  (author’s own)

Now that you know Kombucha is mostly vinegar and tea, you can probably guess that is is rather sour, you’re entirely correct. And unless you particularly enjoy downing straight salad dressing or are a particularly ascetic individual, why on Earth would you drink it? I’ve even heard it described as tasting like a cold sore. Some people do quite like the taste – I imagine the same sort of person that enjoyed Sour-war-heads in primary school. But if it were purely taste and the home-style convenience that attracted people why not just brew your own vinegar? (yes that’s a thing)

You guessed it… it cures cancer. Well, at least, there are claims that it cures cancer.

When I see anything that claims to ‘cure cancer’, I usually smugly ask ‘which type?’, because cancer is a group of diseases and I quite like bringing up the fact that I know about three cancer related acronyms (unless they’re talking about checkpoint blockade, because that stuff is the real deal). Regardless, I think it’s good to be quite skeptical about ‘magic antidotes’ like this, especially in foods, mostly because every person digests and utilises foods quite differently.

And yet, Kombucha has been valued for its healing properties since as early as 220BC China. So why not explore the legitimacy behind these claims? Quite often, stories about traditional medicines end up being fully founded in science and can treat a lot of horrible diseases.

A fantastic review of all current literature into the possible health benefits of Kombucha was conducted in 2014. Most of these benefits were discovered in experimental animals, and there hasn’t been experiments in humans yet, but there seems to be a lot of potential!

The main benefits seem to stem from these four main properties: detoxifying abilities, protection from free radicals (due to antioxidants), increasing blood-oxygen availability and promotion of immunity. And some of the proposed benefits include reducing blood cholesterol, reducing blood sugar, healing gastric ulcers, decreasing absorption of LDL (bad cholesterol), increasing absorption of HDL (good cholesterol), repairing  damage to the liver and reducing the activity of cancers (particularly those fed by hormones).

It seems too good to be true, doesn’t it? Perhaps. Unfortunately, there are also some horror stories. There are cases of hyperthermia, lactic acid poisoning, acute renal failure and liver toxicity, all within 15 hours of kombucha consumption. These are likely due to contamination with pathogenic fungal spores into the scoby and poisoning due to acidic degradation of the container (lead can leech out of ceramics due to acids).


Storing and preparing Kombucha in glass is safe. Image courtesy of JP

Though, these do seem to pale in comparison to 30 proven benefits. I encourage you to wait for more studies about this exciting new area of food science to emerge. With a little more evidence about its safety and effectiveness, Kombucha could transcend the titles of ancient magic fungus tea and weird hipster fad and change the face of health foods and medicine forever!

For more information:

A really great and easy-listening podcast: https://gastropod.com/kombucha-culture/


7 Responses to “What’s the fuzz with Kombucha?”

  1. Caitlin Selleck says:

    This is such a cool topic Lachy! I didn’t realise it was a trend at the moment. I had a friend’s partner making it, all I heard was “SCOBY” and “yeast infection” so it didn’t seem that appealing 😛 Now I actually know what it is, maybe I’ll try it out!

  2. Alina says:

    Cool blog- I was wondering what all the fuss was about. I tried a sip of kombucha once but didn’t quite like the taste- but given the potential health benefits I may reconsider trying it again!

  3. Mei says:

    This was an awesome read! I’ve been following all the hype surrounding kombucha on blogs and at healthy cafes but I noticed a severe lack of a detailed (but easy to understand) explanation of the science behind it. I only knew about it being “fermented tea with many health benefits”. Your piece was super informative and interesting. Love your illustration haha

  4. Maja Dunstan says:

    I never understood what kombucha is! Thanks for the informative post.

    I don’t think I’ll be trying it anytime soon though, not really my cup of tea. But I do ferment my own kefir – which is super nice! The milk version tastes a lot like a runny Greek yoghurt, and is great with cereal or muesli.

  5. eciarrocchi says:

    Awesome post Lachlan!
    When I was a kid my dad used to brew the stuff in a cabinet in our spare room. To me back then, it was like he was some kind of wizard, concocting a potion that he would drink and it would grant him youth, or eternal life or something like that.
    I don’t know if growing up and learning about the science of it all has made me appreciate kombucha more or less. I guess I should try it to find out for myself, haha. Larissa, I might even take you up on your SCOBY offer….

  6. Lachlan Tegart says:

    Hi Larissa!
    Thanks so much for the generous offer, I’m getting some from a friend on very soon, so keen to try making it after reading so much about it!
    I was wondering if you personally brew it for the health benefits, or is it the taste?
    So glad you liked the article!

  7. Larissa says:

    Interesting article! I have to admit I do brew my own kombucha at home. To improve the taste and fizz I put it through a second ferment with raspberries and mint. It adds a lot of flavour and its much more refreshing. It also turn bright pink which is far more appealing than a weird yellow. It was interesting to know that there is no alcohol in the end, I’ve never been sure of that. If anyone would like to experiment with a SCOBY I have plenty 🙂