How To Make Your Own Kombucha Scoby

There’s really no arguing that

scoby is ugly

If you want to save a few bucks on your ‘booch habit, there’s just no getting around it. You’re going to need a scoby.

You can beg a scoby from a kombucha-brewing friend, or you can order a fresh one online. But there’s one more option: you can grow your own. This can be easily done by combining tea, sugar, and some pre-made kombucha. Here’s how to do it.

“Scoby” is actually an acronym: Symbiotic Culture Of Bacteria and Yeast. And that’s exactly what it is.

A scoby is the living home for the bacteria and yeast that transform sweet tea into tangy, fizzy kombucha — think of the scoby as the coral reef of the bacteria and yeast world. It’s a rubbery raft that floats on the surface of the kombucha.

Aside from being a home for yeast and good bacteria, the scoby seals off the fermenting kombucha from the air and protects it from outside, undesirable bacterias while it’s fermenting.

P.S. You’ll also sometimes hear scobys referred to as “kombucha mothers” or “kombucha mushrooms.” If you read or hear references to these things, know that it’s all the same thing.

A scoby is a naturally occurring part of the kombucha brewing process. It’s constantly renewing itself and a new layer of scoby will grow on the surface of the old one every time you brew a batch of kombucha.

You’ve also probably bought a bottle of kombucha with a little blobby thing inside. Well, that’s actually a tiny, newly-forming scoby. This ability of the the scoby to constantly reform itself is what makes it possible for us to grow a new scoby from scratch.

Here are the ingredients you’ll need to make a scoby at home:

• Kombucha: You can use homemade kombucha from a friend or store-bought kombucha, but make sure it’s a raw, unflavored variety. It also helps if you can see one of those little blobby things floating at the top or bottom of the bottle.
• Black tea: Plain black tea is the best and most nutritious tea for scoby growth. For this step of growing a new kombucha, use black tea if at all possible; you can play around with other teas once you start making kombucha regularly.
• Sugar: Scobys form best if you use plain, granulated table sugar. Organic sugar is fine, but avoid alternative sugars or honey.

Part of the job of the scoby is to protect the kombucha while it ferments. This means that a jar of kombucha without a scoby is vulnerable to any bacteria, good or bad, that’s floating around the environment.

• Keep your tools clean. Make sure the jar and utensils you use are squeaky-clean and rinsed of any soap residue.
• Cover the jar safely. Cheesecloth is not ideal because it’s easy for small insects, like fruit flies, to wiggle through the layers. Use a few layers of tightly woven cloth (like clean napkins or tea towels), coffee filters, or paper towels, to cover the jar, and secure it tightly with rubber bands or twine.
• Avoid direct sunlight. Keep the growing kombucha covered and away from direct sunlight.
• Let it sit. Keep the jar somewhere out of the way where it won’t get jostled.
• Keep your hands clean. Wash your hands before touching or handling the scoby.

Keep an eye on your scoby and refer to the photos in this recipe. And keep these sensory details in mind:

• What to look for: Bubbles, jelly-like masses, and gritty brown-colored residue are good.
• Signs to throw it out: Fuzzy black or green spots of mold are bad.
• What it should smell like: The liquid in the jar should always smell fresh, tart, and slightly vinegary (this will become more pronounced the further you are in the process).
• What it shouldn’t smell like: If your scoby smells cheesy, rancid, or otherwise off-putting, then something has gone wrong.

Be safe: if you suspect something has gone wrong, then toss the batch and start a new one. Use your best judgement — though I know this is hard because growing a scoby isn’t exactly something most of us have done before. It’s a weird process! Know that if something is wrong, it will inevitably get worse; if it’s a normal part of the process, it will even out.

All these warning aside, I made new scobys many many times myself and never had it go wrong. There’s a bit of trust involved — it just looks gross! — but I find that if you let it be, it comes out right in the end.

It takes roughly 2 to 4 weeks to grow a new scoby from scratch. The time might be less if your kitchen is warm or longer if your kitchen is cool.

In general, try to keep your kombucha at an average room temperature of about 70°F, and your scoby will form in a little over two weeks.

Once you have a new scoby, you are ready to make your first batch of fizzy, tangy kombucha. Read all about how in this step-by-step guide to making kombucha.

Read more about how to make kombucha from my book, True Brews: How to Craft Fermented Cider, Beer, Wine, Sake, Soda, Mead, Kefir and Kombucha at Home.