Sweet tea, a living starter, and a little patience: that is where homemade kombucha begins. This recipe walks you through a first batch, from brewing the tea to pouring a chilled glass. Expect a pleasantly tart drink with a little sweetness; the amount of natural fizz will vary.

Hands-on time: About 25 minutes
Cooling time: Up to 2 hours
Fermentation: Usually 7–14 days
Yield: About 2.8 litres, after saving starter for your next batch
Measurements: US cups; metric equivalents are rounded

What is kombucha?

Kombucha is sweetened tea fermented with a culture of bacteria and yeast, commonly called a SCOBY. The soft, pale disc supplied with many starter kits is the culture’s cellulose mat, or pellicle. You also need the accompanying fermented starter liquid, which helps acidify the fresh tea. Colorado State University explains the process.

Ingredients

• 12 cups filtered drinking water (about 2.85 litres), divided
• 6 plain black tea bags
• 1 cup white cane sugar (200 g)
• 2 cups mature, unflavoured kombucha starter liquid (475 ml), plus extra if needed for the initial acidity check
• 1 healthy SCOBY from a reputable kombucha starter supplier

Use an active starter intended for brewing. The ingredient proportions are adapted from Utah State University’s homemade kombucha recipe.

Equipment

Gather a saucepan, a food-grade glass jar holding at least 4 litres, a spoon, a thermometer, a calibrated food pH meter, tightly woven clean cotton cloth, and a rubber band. For bottling, use clean bottles designed for carbonated drinks and a funnel.

How to make homemade kombucha

1. Clean your equipment

Wash your hands and work surface. Wash the jar, utensils, and bottles thoroughly, rinse well, then sanitize with a food-contact sanitizer according to its label. Use clean utensils whenever you sample or transfer the brew. Good hygiene matters throughout fermentation. Read the home-preparation safety guidance.

2. Brew and sweeten the tea

Bring 4 cups of the water to a boil in the saucepan. Remove from the heat, add the tea bags, and steep for 10 minutes. Lift out the bags and stir in the sugar until dissolved. This tea-making method follows university extension guidance.

Dissolve the sugar while the tea is still hot.

3. Cool completely

Add the remaining 8 cups of cool drinking water. Let the sweet tea reach about 20–25°C (68–77°F), checking with a thermometer. Use a cold-water bath around the saucepan if needed; aim to finish cooling within 2 hours. Transfer to the clean glass jar. Hot tea can damage the culture, so add the starter only after cooling. BCCDC recommends prompt cooling before inoculation.

4. Add the starter and SCOBY

Stir in the starter liquid and gently add the SCOBY with clean hands or utensils. Leave several centimetres of space at the top of the jar. For this beginner method, check that the mixed tea is at pH 4.2 or below before setting it aside. If higher, add more mature starter and recheck. If you cannot reach that level, obtain a fresh, active starter before proceeding. This conservative starting check uses the recommended acidity threshold for kombucha.

Add both the starter liquid and SCOBY to completely cooled tea.

5. Cover and ferment

Cover the opening with tightly woven cloth and secure it with the rubber band. Keep the jar out of direct sunlight, ideally at 22–26°C (72–79°F). Date the jar and allow 7–14 days. A moist cream-coloured layer can form on the surface as the culture grows. CSU Extension describes this fermentation stage.

From day 7, check the pH before tasting a small sample poured into a clean cup. It should be 2.5–4.2. If it is above 4.2 at day 7, discard the batch and culture; if below 2.5, do not drink it. Within that range, taste daily until pleasantly tart, checking acidity each time. Never return a sample to the jar. Acidity checks complement good hygiene; they do not prove a batch is free of contamination. These limits follow BCCDC safety guidance.

A breathable, securely fastened cover protects the fermenting tea.

6. Bottle, chill, and serve

With clean utensils, reserve the SCOBY and 2 cups of plain finished kombucha for your next batch. Pour the rest into suitable bottles, leaving the manufacturer’s recommended headspace, usually about 2.5–5 cm (1–2 inches). Cap and refrigerate immediately at 4°C (40°F) or colder. Serve chilled and open bottles slowly over the sink. This recipe uses immediate refrigeration; it does not include a sealed room-temperature carbonation stage. CSU Extension includes this bottling option.

Save starter for the next batch, then bottle and refrigerate your drink.

Easy flavour ideas

Add flavour to your glass just before drinking. Try a splash of apple juice, a little mashed strawberry, or a thin slice of fresh ginger with lemon. Start small and adjust to taste. For extra bubbles, top up with chilled sparkling water and serve immediately.

A few important brewing notes

Mould means discard. Dry, fuzzy patches are a warning sign. Discard all the liquid and the SCOBY; do not scrape off the mould and keep brewing. Clean and sanitize the equipment before starting again. CSU explains contamination and safe handling.

Keep finished kombucha refrigerated. Cold slows fermentation but does not sterilize the drink. Fermentation can continue in bottles, producing pressure and alcohol. Homemade kombucha is not reliably alcohol-free and is unsuitable when alcohol must be avoided, including during pregnancy or for children. BCCDC explains the alcohol concern.