How to Make Kombucha: A Step-by-Step Guide

Make-your-own-kombucha

What is kombucha?

Kombucha is a healthy, fermented, and low-alcohol drink. Fermented foods such as kombucha have been shown to positively impact the gut microbiome and even reduce inflammation. Chronic low-grade inflammation is linked to disease development and accelerated aging. By keeping inflammation low and your microbiome healthy, you actively support better long-term health.

Since kombucha is fermented, it contains a very low alcohol percentage—usually under 0.5%. If left to ferment longer in warmer conditions, it can sometimes exceed 1%. That means kombucha is not always suitable for children or pregnant women.

For most people, however, kombucha is very healthy—and delicious!

Kombucha: buy it or make it yourself?

You can buy kombucha in stores, but for maximum health benefits, choose fresh, unpasteurized kombucha in glass bottles. Even better: you can also learn how to make kombucha at home.

What is a SCOBY?

To make kombucha, you need a SCOBY, which stands for:

S: Symbiotic
C: Culture
O: Of
B: Bacteria, and
Y: Yeast

A SCOBY is a living culture of bacteria and yeast that drives the fermentation process. Ideally, you get one from a friend, but you can also buy one in health food stores.

How do you get a SCOBY? Maybe you know someone who brews their own kombucha. They might be able to give you a piece of their SCOBY. Otherwise, you can try finding one online.

How to make kombucha: recipe

This recipe works best if you are starting with a relatively small SCOBY. Avoid doubling the recipe if your SCOBY is still small.

Ingredients

  • 1 SCOBY
  • 150 ml kombucha (from the SCOBY starter liquid or a fresh, unpasteurized store-bought bottle)
  • 1 liter strong black or green tea (preferably organic loose leaf, e.g., sencha)
  • 80 g organic cane sugar

Materials

  • A large glass jar with a wide opening (plastic is possible, but never metal—it reacts with the acids)
  • A cheesecloth or clean cotton cloth to cover the jar
  • A rubber band to secure the cloth

Preparation steps

  1. Clean everything thoroughly: Wash all materials and your hands carefully, ensuring no soap residue remains.
  2. Brew the tea: Boil water, add tea and sugar, and let it steep. Allow to cool completely.
  3. Mix in the jar: Pour the tea into the jar and add the kombucha starter liquid. Gently place the SCOBY on top, light side facing up. It may sink at first but usually floats back up within days.
  4. Cover the jar: Secure the cloth with a rubber band to keep out dust and insects.
  5. Ferment: Place the jar at room temperature (slightly warmer is even better). Leave for at least 5 days before tasting.
  6. Taste daily: Kombucha should develop a balance between sweet and sour. When the flavor is right, bottle it—but don’t fill bottles to the top. Fermentation continues: faster at room temperature, slower in the fridge.
  7. Reuse your SCOBY: It will keep growing and can be used again. If stored, keep it in a few hundred ml of slightly sweet kombucha in the fridge for a few weeks. Without sugar, the SCOBY will eventually die.
SCOBY-Kombucha

How to tell if your kombucha is healthy

✅ Signs it’s going well:

  • A jelly-like layer forms on top
  • Brown residue at the bottom
  • Fresh, light vinegar smell
  • Tiny bubbles

❌ Signs it’s gone bad:

  • Gray-black spots
  • Green patches or mold
  • Rotten, cheese-like odor

Variations: kombucha with grape juice

Try this variation for a fruity twist:

  • 1 SCOBY
  • 1 liter grape juice
  • ½ liter kombucha
  • ½ liter water

Follow the same steps as the regular kombucha recipe.

Tips for the best kombucha

  • If your kombucha tastes too sour, mix it with fruit or vegetable juice. Apple juice or beet juice pair especially well.
  • Always use clean glass bottles for storage.
  • Experiment with teas and flavors once you’re confident with the basics.

Conclusion: learning how to make kombucha

Learning how to make kombucha at home is simple, fun, and rewarding. With the right ingredients and a SCOBY, you can create a delicious, gut-friendly, fermented drink that supports your health and digestion.

Want to improve your gut microbiome even more? Combine kombucha with other fermented foods such as sauerkraut, kimchi, or miso for maximum benefits. Learn more about the gut microbiome and fermented foods here.

Sources

1. Wastyk et al. Gut-microbiota-targeted diets modulate human immune status. Cell. 2021;184(16):4137-4153.

2. Ivory et al. Determination of Ethanol Concentration in Kombucha Beverages: Single-Laboratory Validation of an Enzymatic Method, First Action Method. J AOAC Int. 2021;104(2):422-430. doi: 10.1093/jaoacint/qsaa122.  

3. Dartora et al. Understanding the effect of fermentation time on physicochemical characteristics, sensory attributes, and volatile compounds in green tea kombucha. Food Res Int. 2023;174(Pt 1):113569. doi: 10.1016/j.foodres.2023.113569. 

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