I'm brewing two batches of kombucha, one with a fairly old mushroom that I had in the fridge and one with a newer one from a friend. The one with the old mushroom is growing spots of mold on the surface of the liquid. It's been brewing for a week. Some questions:
Is this because the mushroom is old? I think it was in the fridge for several months, stored in a clean sealed jar with just a little bit of kombucha. It looked, smelled and felt just fine when I got it out.
Maybe it's because I tried to 'fancy up' that batch with ginger? I added about five slices of fresh ginger to the boiling water and left them there through cooling and strained them out when I took out the tea bags and added the mushroom. (I will be bummed if this is the reason! My friend made some absolutely heavenly ginger-infused kombucha and I want to replicate it!)
Maybe it's because the kombucha was not properly covered all the time? I have it on the kitchen counter, covered with an old (clean, obviously!) cloth diaper. My littlest is now old enough to reach the back of the counter from a stool and has pulled the cover off a few times. But the other batch was uncovered, too, and seems fine, so this probably isn't it.
Lastly, what can I do? I sort of assume I'll just have to dump the whole thing, mushroom and all, but what a shame!
Yes you will need to dump the batch with the mold and get rid of the mother. I never brew with anything else but tea and sugar as to not contaminate my mother, it's very possible that the ginger had mold on it and it grew from that, or being uncovered. I always do a secondary ferment if I want fruit or juice in it. I just pour my finished kombucha in a sealable bottle, then add fruit or fruit juice, then seal and let sit out for a few days for a second ferment, then while thats happening I just start a new batch with my mother . I use a large grolsch style bottle for secondary ferment, and I never refrigerate mine, I just add icecubes to mine, mine seems to loose it's fizz if I refrigerate it, of course you have to open it every few days because it builds up pressure, but mine never lasts to long to worry about it. My absolute favorite for my secondary ferment is bing cherries, I take about 8 cherries and half a cup of filtered water in a saucepan, bring to boil, smash the cherries with a potatoe smasher, let boil for a few minutes (I think this might help get rid of possible mold) then strain out cherries, I let cool then add to my kombucha that I added to my grolsch bottle, then let sit for 3-5 days before drinking, yummy!
You don't think that boiling the ginger in the water would have killed any bacteria?
Thanks for the recipe, too....that sounds yummy!
Anyone know how long you can keep a mother in the fridge in a clean and sealed jar?
Never, ever refrigerate a kombucha scoby. It'll encourage mold. If you get mold, the scoby is bad and cannot be saved. It needs to be tossed. Hopefully your other one is growing and can be divided.
You can store unused scobies for a long time in a "scoby hotel" at room temperature.
I wouldn't think the ginger caused a problem. Do you have room in a closet to put the kombucha while it ferments?