Kahm yeast can occur here and there, even with experienced kombucha brewers. Here are a few tips on what you can do:
- A fresh start: Do you still have a scoby with starter liquid as a back-up in the fridge or ready-made kombucha? If so, you can completely discard the batch with the cream yeast, clean your vessel thoroughly with hot water and washing-up liquid and start a new batch with your spare scoby or the finished kombucha as the batch liquid.
- Get rid of the yeast: If you don't have another Scoby, you can try to get rid of the yeast. To do this, take out your Scoby with clean hands and rinse it well to get rid of the yeast.
- Keep about 10% of the finished kombucha as a starter for the next batch, or a little more if the liquid is not yet acidic enough. It is important that the kombucha is well acidified for the next batch. If possible, try to get liquid without pieces of cream yeast, for example from the lower part of the vessel. Theoretically, you can also drink the preparation with yeast without hesitation. If it is too unappetising for you, tip it away.
- Clean your kombucha jar very thoroughly to remove all remnants of cream yeast. Make sure to remove all detergent residues at the end and do not use an old, unhygienic sponge.
- Prepare your kombucha as usual. If you've done any experimenting in the last batch, go back to the standard ingredients: black or green tea and regular household sugar.
- Now watch your kombucha well for the next few batches and prepare it with the normal ingredients. If everything goes well, the yeast will not come back.
- Kahm yeast actually only occurs when the kombucha is weakened. Check your location, your ingredients and whether you have done everything right when brewing.