I recently brewed my first batch of kombucha, and it turned out great, but I was disappointed with the yield. I took the new scoby, transfered it and some kombucha to a new jar, and filled it with more tea. My original jar looks very healthy and happy, but my new jar looks strange. Is this normal, or should I throw it out and start again?
This is the original, healthy batch for comparison.
The brown scum on the first two images could just be tannin from black tea. You can peel this/ the stained layers off the scoby. You can avoid it next time by not letting the tea "stew" i.e. removing the tea bag sooner (you might also need to use a water filter).
You can increase the yield with a bigger container. It needs to have a wide mouth to maximise the amount of surface exposed to air relative to the volume of liquid. I personally find my kombucha too acidic after a week so need to dilute it in a closed secondary fermentation (to fizz up) which doubles the yield.
I'll try that. I'll peel off the brown layer and give it more time.