How to make kombucha at home: your first batch, step by step

What you need

For a first batch of 2 liters, gather the equipment below before brewing the tea. You’ll need room in the jar for the starter liquid as well as the tea, plus space above the liquid. The kombucha equipment guide explains vessel sizes and starter kits. If you haven’t brewed or tasted it before, what is kombucha explains the drink and its fermentation.

Quick checklist for a 2-liter batch

• A wide-mouth glass jar of 3 to 4 liters for this 2-liter-water recipe. Wide is better than tall, because the culture works at the surface.
• A tightly woven cloth cover (a clean tea towel, a coffee filter, or a few layers of cheesecloth) and a rubber band. The cloth lets air in and keeps fruit flies out.
• Plain black or green tea. Loose leaf or bags both work. For the main culture, choose unflavored tea with a clear ingredient list. Test Earl Grey, chai, herbal tea or another blend in a separate small batch, and keep backup starter in plain sweet tea. The best tea for kombucha explains why.
• Plain white sugar. It feeds the culture, but some sugar remains in finished kombucha; the amount varies by batch.
• An active SCOBY culture with sour starter liquid from a healthy batch, obtained from another brewer or a supplier. Measure 100 to 200 ml of starter per liter of water. The culture lives in the liquid as well as in the rubbery cellulose disc, or pellicle; a disc alone doesn’t replace starter liquid. What a SCOBY is explains the difference.
• For the second fermentation, bottles designed to hold carbonated drinks, with sound seals and no chips or cracks.

Use a food-grade glass vessel or food-grade stainless steel. Kombucha’s acidity can draw lead from unsuitable ceramic glazes, so only use ceramics with a glaze confirmed as lead-free and safe for acidic foods. Avoid prolonged contact with reactive metals and any plastic that isn’t food grade. A container meant for decoration or dry storage may not suit fermentation.

The kombucha ratio

Measure the ingredients rather than judging by eye. This recipe uses 5 g of tea (about two tea bags), 60 to 70 g of sugar and 100 to 200 ml of starter liquid per liter of water. Other published recipes use different amounts; keep the proportions from one recipe when you start, rather than combining parts of several. The table scales this recipe to three batch sizes.

Use a reliable starting recipe. The culture needs sugar, but the amount left in the finished drink varies. If you want to try less than 60 to 70 g per liter, change it gradually and check that the batch acidifies normally. A longer ferment can also reduce sweetness.

Use active, sour starter liquid. This is fermented kombucha from a healthy previous batch. It lowers the pH of fresh sweet tea, increasing acidity and helping limit the growth of unwanted microbes while supplying the culture. Measure the amount in the recipe; adding extra liquid doesn’t guarantee safe fermentation or compensate for an inactive or contaminated starter. Check the brew’s acidification as it develops.

How to make kombucha from scratch, step by step

1. Brew the tea

Boil the water and steep the tea for about 10 minutes, as in Colorado State University’s recipe. If you heat only part of the water, use the full measured amount of tea in it and add the remaining water when cooling. Remove the tea bags or strain out the leaves before adding the culture.

2. Dissolve the sugar and cool it down

Stir the sugar into the hot tea until it dissolves completely. Cool the tea before adding the culture: wait for room temperature, below about 30 °C (86 °F), because heat can damage it. To cool the brew faster, make concentrated sweet tea with half the water and add the remaining half cold, as CSU’s guide suggests. Check the temperature after mixing; adding cold water doesn’t necessarily cool it enough.

3. Add the starter liquid and the SCOBY

Pour the cooled sweet tea into the jar, stir in the measured starter liquid and add the SCOBY pellicle with clean hands. A pellicle can float, sink or sit sideways; its position doesn’t show whether the batch is fermenting safely. During fermentation, the culture can form a new cellulose layer at the surface. Follow the souring of the liquid too.

4. Cover and wait

Secure the cloth over the jar with the rubber band. Choose a place between 20 and 26 °C (68 to 79 °F), out of direct sunlight, where air can reach the cover. Keep it away from compost, spoiled fruit and other possible sources of contamination. Record the start date and room temperature, and leave the cover in place between checks.

5. Taste from day 5

Start tasting around day 5 with a clean spoon, without tearing the pellicle. If the brew is still sweet, let it ferment longer and check again. A tart taste with some sweetness left can help you choose when to bottle, but taste alone cannot confirm safety. Discard a batch with mold, an off smell or failed acidification; don’t dilute it to hide a problem. Check the pH guidance below before using a very sour batch as starter. How long to ferment kombucha explains how temperature affects the timing.

6. Bottle it, and keep the next batch going

Before bottling, reserve enough starter for the next recipe: 100 to 200 ml per liter of water you plan to use. Keep the pellicle with that liquid in a clean container. Bottle the remaining kombucha and refrigerate it if you want to drink it without further fermentation. For added fruit and fizz, follow the second fermentation guide and use pressure-rated bottles; a tight lid alone doesn’t make a bottle suitable.

What to expect, day by day

• Days 1 to 2: the brew may still smell like sweet tea, with few visible changes. Bubbles at the edge can appear, but their absence doesn’t tell you whether fermentation has started.
• Days 3 to 5: a thin, translucent film may appear at the surface, sometimes with wet brown yeast strands below it. These can occur during fermentation; they don’t confirm that the batch is safe.
• Days 6 to 8: the new pellicle may thicken and the aroma become more vinegar-like. A cool room or a recently stored culture can delay these changes, so treat these dates as approximate.
• Days 5 to 14: tasting helps you follow the falling sweetness and rising tartness. Use it alongside checks for contamination and acidification before deciding to bottle.

Wet brown yeast strands and an uneven cellulose layer can occur in a fermenting batch. If new layers accumulate, what a SCOBY is explains how to store them. Dry, fuzzy patches need different handling: discard the batch if you find mold. The kombucha mold guide compares its appearance with yeast and cellulose; don’t assume an unfamiliar growth is harmless.

Keeping it safe

Clean equipment, an active starter and proper acidification reduce contamination risks. They don’t make every home-brewed batch safe, and a normal-looking pellicle cannot confirm safety. The BCCDC guidance cited below covers fermentation controls, container materials and excess acidity. Use these checks when preparing and assessing a batch:

• Wash hands and clean equipment with hot water and dish soap, then rinse thoroughly. Follow appropriate sanitizing instructions for utensils and bottles, and avoid cleaners that leave residue.
• Measure starter liquid and check acidification. BCCDC’s processing guidance recommends a finished pH below 4.2 and not below 2.5. A pH measurement adds information that tasting cannot provide, but it doesn’t rule out contamination or measure alcohol.
• Keep the jar covered and the cover clean.
• If you see dry, fuzzy mold, throw the whole batch away, culture included. Never scrape and continue.
• Store finished kombucha in the fridge, and open bottles with care after a second fermentation.

Common first-batch mistakes

• Guessing the starter amount. Measure 100 to 200 ml per liter of water for this recipe, and increase that amount proportionally when you brew a larger batch.
• Adding the SCOBY to warm tea. Wait until the jar feels room temperature to the touch.
• Sealing the first fermentation. The culture needs air, so use a securely fastened, breathable cloth cover; save sealed bottles for the second fermentation.
• Reducing sugar drastically without checking the result. Start with a reliable recipe, make small changes, and make sure the brew acidifies normally.
• Assuming a refrigerated culture is ruined. Cold slows it; keep an active SCOBY hotel at room temperature, and test a chilled culture in a small batch before scaling up.
• Assuming a slow batch will recover on a fixed schedule. A shipped or stored culture may start slowly; check that it acidifies the tea rather than waiting for an expected number of batches.

Where to go from here

For your next batch, use the fermentation timing guide to compare warmer and cooler brewing conditions. The second fermentation guide covers bottling for fizz and flavor. For culture care, read about SCOBY storage, and keep the mold guide available when checking unfamiliar surface growth.

Frequently asked questions