What Is a SCOBY? | Monty Booch’s Complete Guide

If you’ve ever brewed kombucha, you’ve probably noticed that strange, jelly-like disc floating on top of your brew. That’s often called a SCOBY, but the truth is, there’s a bit more to it.

SCOBY stands for Symbiotic Culture Of Bacteria and Yeast. It’s a living community of microbes that transform sweet tea into the tangy, fizzy, probiotic drink we all love: kombucha.

The floating disc (sometimes called a pellicle) is actually a by-product of the fermentation process, a cellulose layer created by the bacteria. The real SCOBY lives throughout the liquid, doing all the hard work of fermentation.

SCOBY vs Pellicle: What’s the Difference?

• SCOBY: The full living culture of bacteria and yeast that ferments the tea.
• Pellicle: The cellulose “skin” that forms on top as bacteria work. It’s part of the process, but not the whole SCOBY.

While the pellicle looks impressive, the actual magic happens in the kombucha liquid, where billions of microbes are busy balancing sweet and sour flavours.

How a SCOBY Works During Fermentation

1. Start with sweet tea (sugar and tea).
2. Add your SCOBY and starter liquid (around 10–30% of the total volume).
3. Yeast in the SCOBY converts sugars into alcohol.
4. Bacteria turn that alcohol into organic acids.
5. A pellicle forms on the surface — a natural sign of a healthy fermentation.
6. After 7–14 days, you’ve got tangy, probiotic kombucha!

At Monty Booch, every brew begins with a healthy, active SCOBY that’s been nurtured through generations — our secret to consistently vibrant, living kombucha.

Brewing Tips for a Happy, Healthy SCOBY

• Use enough starter liquid (around 20% of your previous batch).
• Keep it warm — SCOBYs love temperatures between 22–28°C.
• Avoid metal utensils; use glass, wood, or plastic.
• Watch for contamination — black or fuzzy mould means it’s time to start fresh.
• Always keep a backup SCOBY and some starter liquid.

Why a SCOBY Is So Important

Your SCOBY is the heart of your kombucha. A strong, balanced culture ensures every batch ferments safely and tastes delicious — with the right amount of fizz, acidity, and probiotics.

Think of it like a sourdough starter or kefir grains: it’s a living ingredient you care for and reuse again and again.