Short answer
A SCOBY can sit in starter liquid at room temperature for about four weeks, covered with a breathable cloth. For longer breaks, use a SCOBY hotel and feed the culture every four to six weeks, or dehydrate it. Do not put a living SCOBY in the fridge. Check it for mould before you use it again.
Short breaks (one to four weeks)
Keep the SCOBY in its starter liquid in a clean jar, with enough liquid to cover it. Cover the jar with a tightly woven cloth or paper towel and a rubber band, so dust and fruit flies stay out but air can get in. Keep it out of direct sun, in a room at a steady temperature.
Over a few weeks, the liquid becomes more sour. That is normal. If you return after a month, the brew may taste like vinegar. You can use it in a dressing or marinade, or start a fresh batch with a little of it as starter.
Longer breaks: a SCOBY hotel
A SCOBY hotel is a clean glass jar of kombucha that stores spare SCOBYs between batches.
- Set it up: make a fresh batch of sweet tea, let it cool to room temperature, and pour it into a clean jar. Add the SCOBYs and cover the jar with a cloth. Do not seal it, because the culture needs air.
- Keep it cool: store the hotel in a cool, dark part of the house. Do not put it in the fridge.
- Feed it: every four to six weeks, pour off some of the old liquid and top up with fresh, cooled sweet tea. If you can’t make tea, a little sugar in the liquid can keep the culture going for a few cycles.
- Top it up: liquid evaporates over time, so top up the jar when it gets low.
A hotel can keep a SCOBY for several months. A SCOBY can also get old or die, so check it when you feed it.
Dehydrating a SCOBY
You can dry a SCOBY instead. Lay it on unbleached baking paper in a warm spot, around 26 to 32 °C, until it is dry and leathery, like jerky. Keep flies away while it dries. Store dried SCOBYs in a sealed bag in the fridge, not the freezer. One brewing supplier says they keep for at least three months. To use one again, rehydrate it in sweet tea.
Dry several SCOBYs at once. Some may not come back to life.
Why not the fridge?
Cold slows the culture down, and it can damage it. A SCOBY kept in the fridge can go dormant, and the balance of acid and yeast can shift, leaving the culture open to mould. Keep a living SCOBY somewhere cool and dark at room temperature instead.
Mould versus a normal SCOBY
A healthy SCOBY is cream, tan or pale brown. It can be wrinkled, and it can float, sink or sit at an angle. A new layer can look hazy or thin at first.
Mould is fuzzy or powdery, and can be white, grey, green, blue, black or orange. It can also look like dry, round or misshapen patches. If you see mould, discard the whole SCOBY and the liquid. A dark or old SCOBY can be trimmed, but if you are not sure, throw it out. For more look-alikes, such as kahm yeast and yeast strands, see is it mold or a healthy SCOBY?
Restarting after a break
- Take the SCOBY out of the jar with clean hands.
- Check it for mould. Discard it if there is any.
- Make a fresh batch of sweet tea, cooled to room temperature.
- Add the SCOBY and at least a cup of starter liquid from the jar, or from a healthy batch.
- Cover the jar with a cloth, and leave it out of direct sun for seven to ten days, tasting from day five.
For the starter ratio and the first ferment, see how to flavour kombucha. For the cultures inside the SCOBY, see what bacteria ferment kombucha. For using vinegar as a starter, see can you make kombucha with apple cider vinegar.