What is a SCOBY?

A woman with long hair and jewelry, wearing a beige dress, is holding a jar of honey and dipping a large chunk of beeswax or honeycomb into it in a kitchen.
A woman with long hair and jewelry, wearing a beige dress, is holding a jar of honey and dipping a large chunk of beeswax or honeycomb into it in a kitchen.

If you've just started looking into kombucha brewing, chances are the SCOBY is the thing that both fascinates and slightly terrifies you. It looks weird and it feels weird.

So let's talk about it; what it actually is, where to get one and how to keep it happy.

So What Even Is a SCOBY?

SCOBY stands for Symbiotic Culture of Bacteria and Yeast. Which sounds very scientific, but really it just means a community of living organisms that work together, the bacteria and yeast live side by side, each doing their part to ferment your tea into kombucha.

A SCOBY is both the slimy pancake and the liquid. Which is something a lot of people get confused with. The liquid is technically the most important part and the pellicle is a byproduct of the liquid. Every time you brew, it grows a new layer and that way over time you end up with a thick, layered culture that's full of life.

A hand opening a glass bottle with orange-colored beverage inside, with foam and bubbles around the opening, against a background of a white wall and green plants.
A hand opening a glass bottle with orange-colored beverage inside, with foam and bubbles around the opening, against a background of a white wall and green plants.

Your SCOBY is doing a lot of quiet work while it sits in your jar. The yeast breaks down the sugar in your sweet tea and produces carbon dioxide and a small amount of alcohol. The bacteria then convert that alcohol into organic acids, mainly acetic acid and gluconic acid, which give kombucha its characteristic tang and act as a natural preservative, keeping your brew safe.

The starter liquid acidifies your new batch right from the start, creating an environment that's too hostile for anything harmful to grow. Never skip it, and keep some for your next brew.

What Does It Actually Do?