How kombucha is made

A jellyfish-like mat of bacteria and yeast turns sweet tea sour, and a new mat grows on top every batch.

stations: 5
things upstream: 25
raw sources: 12
steps from the ground: 6

The short version

Kombucha is made by steeping tea in sugar water, cooling it, and adding a living culture of bacteria and yeast along with some already fermented kombucha. The jar sits at room temperature for up to 14 days while the microbes convert sugar into acids and a little alcohol. A new culture mat forms on the surface.

Steep the sweet tea

Sugar is dissolved in non-chlorinated boiling water and tea leaves are steeped in it. The leaves are then removed, leaving sweet tea.

Goes in
Black tea Sugar Water
Cool and add the culture

Once cool, the tea is poured into a sterilized vessel with the culture of bacteria and yeast, called the mother, plus some previously fermented kombucha.
Ferment at room temperature

The yeast turns sugar into alcohol, and the acetic acid bacteria turn that alcohol into acids. A daughter culture forms across the top, growing to the width of the container.

10 to 14 days, 18 to 26 °C
Pull the culture out

The culture is lifted out and stored with a little of the new tea, ready to start the next batch.
Bottle with flavors

Juice, spices or fruit can be added before bottling. The drink carries on fizzing a little in the sealed bottle.

Goes in
Glass bottle

End of the lineKombucha

Worth repeating

The stories that kombucha was served to a Chinese emperor in the Qin dynasty have no evidence behind them.
Dried kombucha culture becomes a leather-like microbial cellulose that can be molded into clothing.
The alcohol content is usually below 0.5 percent but rises the longer the tea ferments.