Fermenting kombucha at home is fun, simple, and rewarding. In this guide, we’ll walk you through everything you need – from equipment and ingredients to the detailed steps of the 1st and 2nd fermentation. Whether you’re a beginner or just looking for some practical tips, this article will help you master the basics.
1. What You Need (Gear & Conditions)
To make kombucha safely and effectively, you’ll need the following:
Glass Jar with Lid: Use a glass jar – it’s ideal for fermentation as it doesn’t react with the acidic brew.
Airflow & Protection: Fermenting kombucha needs airflow. Kefirko Kombucha Fermentor comes with a precisely designed small air opening and activated carbon filter. This setup allows the brew to breathe while preventing contamination and odors.
Starter Liquid and/or SCOBY: You’ll need either a kombucha starter liquid (unpasteurized kombucha from a previous batch) or a SCOBY (Symbiotic Culture Of Bacteria and Yeast) and starter.
Sugar: Cane sugar (white, organic or non-organic) works best. You can experiment with unrefined types like brown sugar, muscovado, or demerara, but they may affect the fermentation process.
Water: Use water that’s safe for drinking. Filtered, tap, or mineral-rich spring water all work well. Avoid distilled water, as it lacks minerals. If the water needs additional minerals, replace ⅕ of the sugar with rapadura.
Tea (Black or Green): Choose pure, additive-free tea, preferably organic (. Avoid flavored or scented teas that may harm your culture.
Environmental Conditions:
Keep out of direct sunlight.
Ferment in a place with good airflow, away from garbage, other ferments, dust, or chemicals.
Ideal temperature: 21–25°C (70–80°F).
2. First Fermentation
If you use only a starter liquid first fermentation will last a little longer because there is time needed for new SCOBY to form at the top (usually it takes from 2 – 3 weeks).
If you have the starter liquid and SCOBY, this lasts from 7–12 days, depending on temperature and other specific conditions.
During this time, SCOBY feeds on the sweetened tea and is transforming it into slightly fizzy, probiotic drink – kombucha.
🧾 Basic Ratio (per 1 liter of kombucha):
10% kombucha starter (100 ml) + SCOBY
20% concentrated sweet tea (200 ml)
70% cool water (700 ml)
50 g of sugar per liter of total liquid
🔪 Step-by-Step Instructions:
Brew a concentrated tea using:
200 ml boiling water
2 tea bags or 2 tsp of loose tea (black or green)
Add 50 g of sugar, stir until completely dissolved.
Let the tea steep for 5–15 minutes (depends on tea type), then strain out the leaves.
Add 700 ml of cool water to dilute the tea. ➤ Hot tea can damage the SCOBY; cold tea may slow fermentation.
Add 100 ml of kombucha starter and your SCOBY. (If you don’t have a SCOBY yet, the starter will grow one during fermentation.)
Cover the jar with a breathable cloth or use the Kefirko fermentor with the air filter. ➤ Do not seal it airtight – fermentation requires airflow. ➤ Make sure flies or contaminants can’t enter.
Let it ferment at 21–25°C for 7–12 days. ➤ Warmer = faster fermentation; cooler = slower. ➤ Start tasting after day 5. Once it reaches your preferred balance of sweet and tangy, it’s ready.
Once done, remove the SCOBY, save 10% of the liquid as starter for your next batch, and either refrigerate your kombucha or continue to the second fermentation.
3. Second Fermentation ( Optional, but Delicious!)
This step is for adding flavor and developing carbonation (bubbles). It also helps reduce remaining sugar.
Key points:
SCOBY is NOT used in second fermentation.
Use airtight bottles.
Add fruits, herbs, ginger, spices, juice – anything you like.
Let it sit at room temperature for 2–5 days, then refrigerate.
Once your SCOBY is strong enough and you want to enjoy kombucha regularly, switch to continuous fermentation. This method always leaves about 20% of kombucha in the jar to act as a starter for the next batch. With this approach, you can enjoy fresh kombucha every 2–3 days, depending on your taste. The more kombucha you leave in, the faster the next batch will be ready.
Benefits:
Faster fermentation time
Fresh kombucha always available
Easier SCOBY maintenance and growth
The Kefirko Kombucha Fermentor is perfect for this method – convenient for daily use and great for picnics.
