What is kombucha? It is a fermented tea made by adding a SCOBY — a living culture of bacteria and yeast — to sweetened black or green tea and letting it ferment for one to four weeks. During fermentation, the culture consumes most of the sugar and converts it into organic acids, natural carbonation, and a trace of alcohol, usually under 0.5%. The result is a lightly fizzy, tangy tea that tastes something like a cross between sparkling apple cider and a dry white wine.
That's the short answer. If you've searched "kombucha tea," "kombucha drink," or just "what is kombucha," you've probably noticed that a lot of what comes up when you ask what is kombucha is either a decade-old blog post or a sales page. This one is neither — it's a straight explanation of what the drink actually is, how it's made, and where the "kombucha tea" and "kombucha drink" terms fit in, before we get to how Aboocha brews its own.
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What Is Kombucha, Exactly?
Kombucha is sweetened tea that has been fermented by a SCOBY (Symbiotic Culture Of Bacteria and Yeast) — sometimes called a "mother." The yeast in the culture breaks down sugar into alcohol and carbon dioxide, and the bacteria then convert much of that alcohol into organic acids, chiefly acetic acid (the same acid in vinegar) and gluconic acid.
What's left after fermentation is a drink that is naturally carbonated, mildly tart, low in sugar relative to what you started with, and very low in alcohol — typically well under 0.5% by volume, which is why it's usually sold as a non-alcoholic beverage.
Some people search for "kombucha tea" and others just say "kombucha" — they mean the same thing. The "tea" in the name isn't decorative: real kombucha starts from actual brewed tea (black, green, oolong, or a blend), because the tea leaves provide nutrients the culture needs and tannins that shape the final flavour. A product fermented from sugar water with no tea at all wouldn't really be kombucha, whatever the label says.
Where Did Kombucha Come From? The History Behind What Is Kombucha
The history of what is kombucha is genuinely uncertain: and most credible sources are upfront about that rather than inventing a tidy founding myth. It's widely believed to have originated in East Asia — Northeast China or Manchuria is the most commonly cited region — sometime in the last two millennia, before spreading along trade and migration routes through Russia and Eastern Europe and eventually into Western Europe and North America over the 20th century.
Along the way it picked up different names in different places, and the version most people know as "kombucha" today only became a mainstream commercial drink in the West from the 1990s onward. Treat any article that gives you a precise year and inventor with some scepticism — the honest answer is that kombucha is old, its early history wasn't well documented, and it travelled a long way before it got here.
How Kombucha Is Actually Fermented
At the centre of every batch of kombucha is the SCOBY. It's worth pausing on this because it's one of the most commonly searched — and commonly misunderstood — parts of kombucha.
What Is a SCOBY in Kombucha? What Does SCOBY Mean?
In any explanation of what is kombucha, SCOBY stands for Symbiotic Culture Of Bacteria and Yeast. It's the rubbery, pale disc that forms on top of a batch of fermenting tea — not a single organism, but a community of several yeast and bacteria species living together, each doing part of the fermentation work.
The yeast converts sugar into alcohol and CO₂; the bacteria then convert that alcohol into the organic acids that give kombucha its tang. Brewers often call it "the mother," because a healthy SCOBY grows a new layer with every batch, and that new layer can be split off to start another ferment. A SCOBY isn't a mould or a sign anything has gone wrong — it's the whole reason kombucha is kombucha rather than just sweet tea.
Primary and Secondary Fermentation
Most kombucha is brewed in two stages:
- Primary fermentation: sweetened tea and a SCOBY sit together, usually for one to two weeks at room temperature. This is where most of the sugar is consumed and the tea turns tart and lightly effervescent.
- Secondary fermentation: the base kombucha is strained off the SCOBY, often mixed with fruit, herbs, or spices, and sealed in bottles for a few more days. Sealing traps the CO₂ the culture keeps producing, which is what builds up the fizz you get when you crack open a bottle.
This two-stage process is why kombucha's carbonation is natural rather than injected — the bubbles are a fermentation by-product, not something added afterward. It's also why flavour and fizz vary a little batch to batch: you're working with a living culture, not a fixed recipe. If you want the fuller mechanics — timing, temperature, troubleshooting a slow ferment — our homebrewer's guide to how kombucha is fermented goes deeper, and our piece on what a SCOBY is and how to care for one is a good next read if you're curious about brewing your own.
What Is Kombucha's Taste and Why Does It Taste That Way?
What is kombucha's tartness? It comes from the organic acids the bacteria produce during fermentation — mainly acetic acid, along with smaller amounts of gluconic and other acids. The longer the ferment runs, the more sugar gets consumed and the more acidic (and less sweet) the kombucha becomes, which is why a two-week ferment tastes noticeably sharper than a five-day one.
The fizz, as covered above, comes from CO₂ trapped during secondary fermentation, not from a soda gun. And any residual sweetness is simply the sugar the culture hasn't gotten to yet — which is also why sugar content varies between brands and even between batches of the same brand.
So what is kombucha like to drink for the first time? Expect something between sparkling tea and a mild, fruity vinegar drink: tangy, lightly sweet, and fizzy rather than heavily bubbly. Plain kombucha leans sharper and more tea-forward. Fruit and botanical versions soften the tartness, which is why flavoured bottles are an easier first taste.
If you want the gentlest start, look for a flavour with a little more fruit and a little less acid. Our Mango Jasmine is the sweetest in the range, still at roughly 1-3% sugar like the rest, and the Original shows you the plain tea-and-tang profile. Our tasting notes guide goes flavour by flavour.
What Is Kombucha Made Of? What's Actually in a Bottle
Set aside the marketing claims for a moment and look at what fermentation actually leaves behind:
| Component | Where it comes from |
|---|---|
| Live cultures | Residual yeast and bacteria from the SCOBY that survive into the finished drink |
| Organic acids | Acetic, gluconic, and other acids produced as the culture ferments the tea |
| Residual sugar | Whatever sugar the culture hasn't consumed by the time it's bottled |
| Natural carbonation | CO₂ produced during fermentation, trapped in a sealed bottle |
| Trace alcohol | A fermentation by-product, typically under 0.5% ABV |
| Tea compounds | Tannins, caffeine, and antioxidant compounds from the base tea |
That's a factual snapshot, not a health claim. Kombucha contains live cultures because it's fermented, in the same way yoghurt or kimchi does — but what any individual food or drink does inside your body is a different question from what's in the bottle, and one that a product label can't answer for you. If you're weighing kombucha against other options, it's worth reading the label on whatever bottle you're holding rather than a generic claim on the internet, this one included.
Is Kombucha Good for You? What Is Kombucha's Evidence Base?
Kombucha is marketed with a long list of health claims, so it is worth being precise about what research does and does not show. A 2019 systematic review searched the literature up to July 2018 and found just one study reporting empirical research on kombucha in human subjects, noting that the many claimed benefits come mostly from non-human research and still need testing in clinical trials.
A 2023 systematic review pooled 15 in vivo studies on gut microbiota and obesity-related outcomes and reported a beneficial association. That is encouraging, but it is not the same as proof that drinking kombucha will do the same for you.
The fair summary: what is kombucha good for is, first, a flavourful, lower-sugar alternative to a soft drink. Health benefits for people are plausible but unproven, and nothing here is medical advice.
Is Kombucha Alcoholic? What Is Kombucha's Alcohol Content?
Fermentation always produces some alcohol, so the honest answer is "a little". The US Alcohol and Tobacco Tax and Trade Bureau (TTB) treats kombucha that reaches 0.5% alcohol by volume (ABV) as an alcohol beverage, and its guidance notes that fermentation can continue in the bottle. Kombucha sold as non-alcoholic is therefore typically labelled below 0.5% ABV, which is the figure Aboocha states for its range.
We have not verified a specific Singapore rule on labelling kombucha ABV, so we do not claim one. Raw bottles that warm up can keep fermenting, so keep them cold. If you are asking because of driving, medication or personal reasons, read our guide on kombucha, alcohol and driving.
Who Should Be Careful With Kombucha?
Aboocha's kombucha and jun tea are raw and unpasteurised, which keeps the live culture but also means they are not for everyone. We suggest them for adults and older teens. We do not suggest them for young children or during pregnancy, and people who are immunocompromised or taking medication should ask their doctor first.
Our guides on kombucha and pregnancy, kombucha for kids and kombucha and medication cover what evidence exists and what it does not show.
How to Drink Kombucha for the First Time
Once you know what is kombucha, the practical question is how to start. Serve it cold, begin with a small glass, and notice how you feel before drinking more. Do not use it to replace water, and remember it is acidic, so a rinse with plain water afterwards is sensible (see kombucha and teeth).
Keep raw bottles refrigerated, as explained in does kombucha need refrigeration. For pacing, see our beginner's guide and how often to drink kombucha.
How to Read a Kombucha Label
Knowing what is kombucha also means knowing what a good label tells you. Look for the serving size, total sugars, whether it is raw or pasteurised, a stated ABV, and how long it was fermented. Our guide on how to choose kombucha walks through each of those checks.
Is Homemade Kombucha Safe?
Many people ask what is kombucha at home and whether they can brew it. You can, but home brewing adds variables a commercial producer controls: hygiene, temperature and how acidic the batch gets. If you try it, follow a tested method and discard any batch that smells or looks wrong. Our homebrewer's guide covers the process in detail.
Kombucha vs. Jun Tea: What's the Difference?
Jun tea is often described as kombucha's gentler sibling, and for anyone asking what is kombucha versus jun, the comparison is a fair one because the process is nearly identical — a SCOBY, two fermentation stages, natural carbonation. The difference is in the inputs. Kombucha is traditionally made with black or oolong tea and cane sugar; jun swaps in green tea and raw honey.
Honey ferments faster and produces a lighter, less tart, often slightly floral result compared to kombucha's deeper, more vinegary tang. Jun also tends to need a shorter, gentler ferment, which is part of why it's less common commercially — it's fussier to brew consistently at scale. If you want to taste the difference rather than just read about it, our jun tea page covers how we brew ours and what to expect flavour-wise.
How Aboocha Brews Its Kombucha
Everything above about what is kombucha is true of kombucha generally. Here's specifically how we do it. Aboocha brews small-batch kombucha and jun tea in Singapore, from black and oolong tea, organic cane sugar, and a single mother culture we've kept alive for years. We ferment long enough that the culture works through most of the sugar before bottling — every bottle is unpasteurised, so the live culture and fermentation flavour you're reading about above are still genuinely in there, not heat-treated away.
Every label carries a Nutri-Grade A–B rating, sits at roughly 1–3% sugar, and is vegan, gluten-free, and dairy-free. Flavours lean toward what we grew up drinking rather than the usual kombucha line-up — sour plum, blue pea and lemongrass, yuzu osmanthus — built on real fruit and botanicals rather than flavour syrups. You can read more about how the brand started, and where the name comes from, on our story page.
If you've read this far because you wanted to actually understand kombucha before buying any, that's exactly the order we'd recommend doing it in. When you're ready to try it, shop our kombucha — or if the honey-and-green-tea version sounds more like your speed, start with jun tea instead. And for a sense of what the different flavours actually taste like once you're past the "what is it" stage, our tasting notes guide is a useful next stop.
Frequently Asked Questions
Is kombucha alcoholic?
Kombucha contains a trace amount of alcohol as a natural fermentation by-product, typically under 0.5% ABV — the same threshold used to classify drinks like non-alcoholic beer as non-alcoholic. It isn't brewed or sold as an alcoholic beverage.
What is kombucha: just fizzy tea?
Not quite. It starts as sweetened tea, but fermentation by the SCOBY changes its chemistry — consuming sugar, producing organic acids, and generating natural carbonation — so the finished drink is meaningfully different from tea with bubbles added.
What is kombucha's SCOBY, and what does SCOBY mean?
SCOBY is an acronym for Symbiotic Culture Of Bacteria and Yeast — the living culture that ferments sweetened tea into kombucha.
How is kombucha different from jun tea?
Kombucha is fermented from black or oolong tea and cane sugar. Jun tea uses green tea and raw honey instead, which generally makes it lighter, less tart, and faster to ferment.
Does kombucha have caffeine, and what is kombucha's tea base?
Yes, in small amounts — it comes from the base tea and carries through fermentation, though typically at a lower level than a cup of brewed tea or coffee.
What is kombucha: a drink or alcohol?
It is a drink. Fermentation produces a small amount of alcohol, and kombucha sold as non-alcoholic is typically labelled below 0.5% ABV, the US regulatory line between a soft drink and an alcohol beverage.
What happens when you first start drinking kombucha?
Most people notice the tang and the fizz. Because it is acidic, fermented and carries a little caffeine, start with a small serving and see how you feel. If you notice discomfort, stop and talk to a doctor.
Is it okay to drink kombucha every day?
There is no official daily amount for kombucha. A small serving is a sensible start; our guide on how often to drink kombucha explains how to pace it.
Does kombucha need to be refrigerated?
Raw, unpasteurised kombucha should be kept cold, because the culture keeps working at room temperature. See our guide on refrigeration.
