Kombucha Troubleshooting: Heat waves and brown glass

Hi! I have two questions.

I have read that I should be keeping my kombucha away from direct light and from heat. My friend and I are both making kombucha in Berlin. We are in the middle of a slight heat wave right now and a few of my friend's kombuchas are not really fermenting at all. They taste mild and not like the initial fermenting days usually do, and they've been in for a week or so. One of her other mothers has grown a dark brown spot on the top on the air exposed side and tastes off. Mine have grown a few white bumps about the size of a 1Euro coin. Is anyone making kombucha in a hot place and has experience with the effects of ambient heat on the mothers? Is there a chance we are killing our SCOBYs or producing potentially dangerous kombucha?

Another note: I have been making some of my primary ferments in brown glass 1 liter milk bottles in order to block some of the light going in. But I can't tell if changing the color of the glass and reducing the surface area of the exposed liquid is maybe damaging my SCOBYs. Maybe they aren't getting enough oxygen. Does anyone have any feedback on using brown glass?

  • Posted by: Olive
  • July 8, 2015


steve July 8, 2015
Hello - I agree totally with the previous contributor - SCOBY's can get spotty and be weird, but it's all normal unless it grows mold (and it's obvious) or I've also had fruit flies lay eggs, so keep a tight cloth over the top. I doubt the color glass makes a difference, some sunlight won't hurt, but hours of intense sunlight giving a greenhouse effect will be terrible. Heat should speed up the fermenting process quite a bit.
Susan W. July 8, 2015
Usually fermentation happens faster in heat. Is it possible that it's over fermented to vinegar? It doesn't sound like it by the taste you describe. Mine takes longer than a week. I don't usually even try it for 10-14 days. The only spots you need to worry about are blue, hairy spots. Mine often have brown or white spots.

I don't think the glass color will affect your SCOBY at all. Many people use ceramic vats. The small neck makes me wonder if it's getting enough oxygen. Here is a website where I learned everything Kombucha. Their FAQs are super helpful.

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