Very fizzy Kombucha

I made some kombucha with mostly decaf and a couple caf green tea bags. On Day 8 it tastes sweet/tart tastes ok. The scoby looks good. But it is very fizzy, more so than even after bottling and letting former batches sit a couple days. It foams up when I pour it in a small pitcher in preparation for filling the bottles. Is this ok? Why is it so fizzy, anyone know? It tastes ok and don't think I taste alcohol. It's maybe a little lighter tasting than with the black tea.

Temps were about 75 - 88 F I think.

Yeast.

They are everywhere, and once they get going in a vat of liquid they like, they will make it quite fizzy. Ever go on vacation and leave a half-empty container of orange juice in the fridge for a week? It will go fizzy too, and you won't be needing any champagne to turn it into a mimosa. But being as there probably wasn't a whole lot of sugars in the starting mash, you're not going to have much alcohol in there, that's why you are not tasting it.

John, is it still ok to drink? Will refrigerating it make a difference? I used the remainder to start a new batch, making some more tea, etc. Should I not have used it? Will the yeast affect the scoby? Sorry for all the questions. I'm new to this. It's only my 3rd batch.

Some yeasts are probiotic, including the Y in scoby. Kalm yeast in a sauerkraut is also probiotic. I can't identify this particular yeast, so I can't answer specifically.
John S
PDX OR

Joanne McCartney wrote:John, is it still ok to drink? Will refrigerating it make a difference? I used the remainder to start a new batch, making some more tea, etc. Should I not have used it? Will the yeast affect the scoby? Sorry for all the questions. I'm new to this. It's only my 3rd batch.

You'll only know after you take a sip.

John has given the technical answer, you don't know until you have identified this particular yeast down to species. But unless there has been a history locally of a problem, like a yeast infection that required medication to treat, I would go on the assumption that it is no big problem. I drink orange juice after it has gone fizzy, and I have yet to regret it. Does it give the kombucha an off taste?

This just goes to show that we share the world with the microbes around us. And a lot of the time, we are ingesting those same microbes. Whether a microbe makes a food unsafe to ingest or if it is still "ok", depends on how hungry you are. Blue cheese and natto are two foods taken over by microbes, and they actually improve the health value of the food. On the other hand, meat that is left out at room temperature too long is going to be bad news.

If you refrigerate your fizzy kombucha now, you are going to slow down your yeast culture, perhaps sending them into dormancy -- until you warm them up and add more sugars, then they will be back to making more fizz. And yes, they probably are in your new batch. It's going to be difficult to separate your kombucha critters from the mysterious yeast X, and the best advice would be to start fresh. Maybe someone with better microbiology lab technique than I can make some suggestions.

If you want to avoid this in the future, I would recommend cleaning your kombucha brewing utensils thoroughly with bleach. Homebrewers (of beer) know this well, that bleach is death on yeasts, and you have to rinse especially well or you run the possibility of killing the yeast that you intentionally add to your brew.

Thank you for your reply, John. I drank about 4 ounces of it that's been refrigerated overnight and it tastes fine. Just a nice light fizz, maybe just a little more than normal. I'll see if it has any effect on me. I didn't die from what I drank yesterday, also a small amount. I have a half galln container that is still brewing which seems very fizzy too. I may let it go another day or two and see what happens.

I used the scoby from the fizzy one to make another batch yesterday. I guess I should probably throw that out. But I hate to dump the scoby. I grew the scobies from part of a bottle of commercial stuff and it took over a month. The one I'm using now is the baby and grand baby of that one. It looks so nice and healthy that I would hate to start over. I don't suppose just washing it with clear water and starting over would help?

The cheesecloth I used for these two batches was a little thin. I wonder if that would have let in more undesirables?

Joanne McCartney wrote: I don't suppose just washing it with clear water and starting over would help?

I don't think so. These yeasts we are talking about are not much bigger than white blood cells. They float through the air with the greatest of ease and can hide in really tiny places on your scoby. If they have decided this is a good place to set up camp and get into a commensal relationship with some Kombucha fungi, they are going to be very hard to evict.

But look on the bright side, you can be the first on your block with naturally carbonated Kombucha. Add some sugar to it, and they may even give it a bit of a kick.

John Elliott wrote:

Joanne McCartney wrote: I don't suppose just washing it with clear water and starting over would help?

I don't think so. These yeasts we are talking about are not much bigger than white blood cells. They float through the air with the greatest of ease and can hide in really tiny places on your scoby. If they have decided this is a good place to set up camp and get into a commensal relationship with some Kombucha fungi, they are going to be very hard to evict.

But look on the bright side, you can be the first on your block with naturally carbonated Kombucha. Add some sugar to it, and they may even give it a bit of a kick.

I'm thinking I'll just keep it going. Actually the fizz is nice and the taste is good. It's still got a little sweetness to it. I drank some more tonight. I guess I'll see what happens. If you don't see me here again you'll know what advice to give the next person with fizzy kombucha on the first ferment. Come to think of it my tongue feels a little prickly. Probably just the power of suggestion. Or maybe it's because of the salt and vinegar potato chips I ate last night.

Kombucha with a good fizz to it is the only kind I know, been doing it two years and every batch turns out basically the same, though more or less acidic depending on the duration and temperature. Natural fizz makes it nice and refreshing, Learned about it a couple years ago to replace light beer and soda/iced tea which was doing me in slowly. No going back to that nasty stuff.