How to Brew Your Own Kombucha

All you need to make this fizzy fermented drink—and reap its health benefits—is a starter, black tea, and sugar.

Your home-fermented kombucha will be ready to drink in two weeks. Jennifer McGruther

If you’ve stepped into a health food store any time in the past decade, you’ve likely noticed the rows of brightly labeled kombucha bottles in the refrigerated section. Once a niche beverage enjoyed by health-conscious hippies, this effervescent fermented tea has exploded in popularity in recent years, fighting its way from obscurity to trendy cafés, cocktail menus, and your local supermarket.

While kombucha has skyrocketed from the obscure to the mainstream, its origins remain murky.

According to Hannah Crum, author of “The Big Book of Kombucha” and founder of Kombucha Kamp, “Kombucha’s origins trace back over 2,000 years to ancient China, where it was revered as the tea of immortality.”

From there, kombucha traveled along trade routes to Eastern Europe and beyond.

Starter cultures were passed from one generation of brewers to the next, often within families or tight-knit communities. This practice ensured that the tradition of brewing kombucha endured for thousands of years, with each batch connecting the present-day brewers to both the past and the future.

What Is Kombucha?

At its core, kombucha is fermented tea.

You start by sweetening black tea with sugar before adding a SCOBY (symbiotic culture of bacteria and yeast). The SCOBY is a thick gelatinous structure brimming with beneficial bacteria and yeasts. The SCOBY and a little brewed kombucha from a previous batch inoculate sweetened tea with the microorganisms it needs to transform into a fizzy tonic.

The fermentation process gives kombucha its distinctive sweet-tart flavor and enriches it with organic acids, B vitamins, antioxidants, and probiotics.

Health Benefits

Health-conscious consumers have flocked to kombucha for its reputed benefits. While research is ongoing, many kombucha enthusiasts report better digestion, blood sugar regulation, and enhanced energy. Kombucha is packed with antioxidant compounds and probiotics; some research suggests these compounds are responsible for the drink’s reputed benefits.

A 2021 study published in Nutrients found that the bacterial strains in kombucha that help transform sweet tea into organic acids support metabolic health and blood sugar regulation.

These findings were echoed in a 2023 study published in Frontiers in Nutrition in which researchers found that drinking kombucha was associated with lowered blood sugar levels in people with diabetes.

The beneficial microorganisms found in kombucha may also support gut health. A 2021 systematic review published in Critical Reviews in Food Science and Nutrition suggests that kombucha alters the gut microbiome while also reducing oxidative stress and combating inflammation.

While these benefits are promising, it’s essential to consume kombucha in moderation, starting slowly with small amounts and enjoying the drink in the context of an otherwise nutrient-dense, wholesome diet.

How to Make Kombucha

Making kombucha at home is rewarding and cost-effective. You need water, black tea, granulated sugar, and a SCOBY with starter kombucha. As brewers gain experience, they often experiment by swapping tea types, adjusting sweeteners, or adding herbs and fruit juices.

Begin by brewing black tea, letting it steep for five to 15 minutes based on desired strength. Stir in sugar while warm, then let it cool completely—adding a SCOBY to hot tea can destroy beneficial microbes.

Pour the cooled tea into a clean glass jar, add the SCOBY and starter tea, then cover with breathable fabric secured by a rubber band. This prevents contaminants while allowing airflow.

Fermentation takes about a week to 10 days, depending on the desired taste. Keep kombucha away from temperature fluctuations. As Hannah Crum noted: “When you give an organism what it needs to thrive, it will! In kombucha’s case, that means keeping it at a temperature of 75 to 85 degrees F, with 80 degrees F being the sweet spot.”

During fermentation, the SCOBY consumes sugar, creating a more sour kombucha. After a week, taste it with a straw. If it is too sweet, let it ferment longer, checking every few days.

As you wait, watch your SCOBY. You’ll notice that it begins to thicken and may separate as the kombucha ferments, producing a second SCOBY. This is a good sign that your kombucha is ready, and you can compost this extra SCOBY or share it with a friend interested in brewing.

To bottle, remove the SCOBY and place it in a clean jar with a cup of kombucha for your next batch. If not using it right away, store it at room temperature away from direct light and heat for up to six weeks. Stir the remaining kombucha, bottle it, and let it sit at room temperature for a day or two to develop fizz before chilling.

A SCOBY, or symbiotic culture of bacteria and yeast, inoculates the tea with the microorganisms it needs to transform. chomplearn/Shutterstock

Mixing It Up

One of the joys of making kombucha is experimenting with flavors. During bottling, you can add fruit juices, herbs, or spices to enhance its taste. Berries create vibrant colors and fruity notes, while ginger adds a complementary zing and supports digestion.

To flavor kombucha, stir about one-fourth cup of fruit juice or herbal syrup into a quart of prepared kombucha tea. Stir it well and transfer it to bottles. Seal the bottles tightly and allow them to sit at room temperature for two days before transferring to the fridge for another two days before opening.

Troubleshooting Your Brew

Even experienced brewers encounter occasional issues when making kombucha. Most of these issues can be prevented by using clean equipment, covering your kombucha with a cloth lid to prevent contamination by stray debris, and keeping it at an optimal temperature.

Nevertheless, pay close attention to the health of your SCOBY. If you notice black or blue spots on the surface of your kombucha, these spots, while rare, likely signal mold formation. Discard your kombucha and SCOBY and start fresh with clean equipment and a new SCOBY. You may also see long murky strings clinging to the bottom of your SCOBY. While these look alarming, these are spent yeast and a good sign of successful fermentation.

While you can get the benefits of kombucha from any store-bought bottle, making your own is a fun experiment. You’ll also be participating in a brewing tradition that has spanned millennia.

Where to Find Supplies

Kombucha Kamp sells live kombucha SCOBYs with starter tea, kombucha kits, and accessories at KombuchaKamp.com

Cultures for Health sells kombucha SCOBYs and brewing kits at CulturesForHealth.com

The Kombucha Shop sells kombucha brewing kits at TheKombuchaShop.com

Basic Kombucha

Makes about 3 quarts (about 12 servings)

• 12 cups water
• 1/4 cup loose-leaf black tea, such as Assam
• 2 cups sugar
• 1 kombucha SCOBY
• 1 cup prepared kombucha

Bring the water to a boil. Turn off the heat and stir in the tea and sugar. Continue stirring until the sugar dissolves completely. Allow the tea to sit undisturbed for about 10 minutes.

Strain the tea through a fine-mesh sieve into a clean, gallon-sized glass jar, and let it cool to room temperature (about 80 degrees F). Add the kombucha SCOBY and the prepared kombucha tea to the jar.

Cover the jar loosely with breathable fabric secured by a rubber band and allow it to ferment at room temperature for about 7 to 10 days. The SCOBY will thicken and may separate, producing a second SCOBY, a good sign that the kombucha is ready. You can also test the kombucha by slipping a straw beneath the SCOBY and taking a sip. When it tastes pleasantly sour-sweet, it’s ready.

Gently remove and reserve the SCOBY, along with 1 cup of kombucha, for your next batch. If not using it right away, store it in a clean jar at room temperature, away from direct light and heat, for up to 6 weeks.

Stir the remaining kombucha well. (If making flavored kombucha, stir in desired flavorings now.) Pour into flip-top bottles, close the bottles tightly, and allow them to ferment another 2 days at room temperature.

Transfer to the fridge for 2 days to allow the bubbles to set before opening. Enjoy within 6 months.