Fermentation Support Forum

I was just wondering if anyone knew why the standard advice online is to chuck the whole batch of kombucha if you find some mould growing on the top of the scoby?

Seems like the same principle as with sauerkraut could apply: if there is a baby scoby growing across the top of the brew and the mould is just on top of that scoby, it likely won't have penetrated into the drink itself, and the original mother (if submerged lower down in the brew, separate from the baby) should be fine, right?

I have just started brewing kombucha so I don't have any spare mothers, and I have what looks like the beginning of white fuzzy mould on top of the baby scoby growing across the surface of the jar. It's hard to say for sure right now if that's what it is, so I'll give it a few more days, but it would definitely be a shame to have to toss EVERYTHING and buy a new scoby

Whenever even a small patch of mould develops, it really is advised to throw everything out. The reasons for this probably are that the mould is already wide-spreaded (on the microscopic level) and the production of the toxins getting into the batch. I don't recommend trying to save the scoby for health safety reasons.
Just to be sure and you probably did it right, to prevent getting mould one must add a small amount of the kombucha beverage together with the scoby when starting a new batch. It happened to me, too .

You don't need a SCOBY to make kombucha, it's a byproduct. In your case, I'd fish it out, toss it in the compost, and see what happens in the jar from there. If more mold forms, you might have to toss the whole batch and start over by combining a commercial kombucha with a jar of sweet tea, but if no more mold forms, it's safe enough for *my* standards. But I'm less mold-risk-averse than some people are and you have to decide for yourself where you sit on that issue.

I agree I'm maybe a bit paranoid about mouldy anything, but I'm a doctor. Guess that explains my attitude.