Sunday, March 11, 2007

Culturing Kombucha from a Commercial Bottle

I got a comment on this, I didn't really give enough detail on exactly how I went from a bottle of Tea Chi to having a gelatinous disk of microbes. Essentially, I applied the same principles to get it that you can to harvest yeast from a commercial beer, start small and go bigger as the microbes can handle it. If you go too big too fast the microbes will take a long time to grown and ferment and might get overrun by the local microbes who might not make such a tasty beverage.

I let the whole bottle of Kombucha warm up to room temperature, I then poured it into a sanitized mason jar. I generally don't sanitize now but I wanted to give the microbes a head start because they might be weak after being refrigerated for a couple of weeks. To them I added about a cup of cooled unfermented Kombucha (just cooled tea with .75 oz of white sugar dissolved in it). Every few weeks I would add some more of this sweetened tea moving up to larger vessels when needed until the Kombucha “mushroom” had grown quite large. I dumped out this first batch because it had gotten very sour because of how long the culture had been fermenting without a large replacement or liquid.

When it gets big enough you can just start bottling 90% of the liquid before adding the fresh nutrient solution.

16 comments:

Zeke said...

I picked up a bottle of kombucha from Kowalski's Market in St. Paul, MN. I'm going to try making it myself when I get home tonight.

The Mad Fermentationist (Mike) said...

How did it go? (not that you'd really have results yet)

Ted Danyluk said...

Can't remember how I fell upon your site...either through searching about brett or kombucha. Your posts and activities are great and enjoyable to read about. Great photos too.

I decided to try propagating my own kombucha culture, and followed your process. It seems to be working well. I'll be posting about it very soon. Was wondering if I could include a link to your site in the post?

Your experiences with funky beers using brett and lambic yeasts are impressive too. I've got an old ale thats sitting on Lambic blend for many months now. It makes brewing much more interesting and mysterious.

The Mad Fermentationist (Mike) said...

Sorry for not responding to this sooner. Glad you enjoy the site, and I’d be honored to be linked to. Good luck with the old ale, I just tried the first bottle of my old ale with brett C (probably the funkiest beer I have made, definitely looking forward to seeing how it ages). The lambic blend in yours will be interesting, should be a complex mix of flavors when it is finished.

Bea said...

I bottled some from GT Dave's, which I got in SF (I live in the Philippines).

I culture Tibicos, and kind of did some shot in the dark here, with raw sugar and water. Now I've given away pretty much a truckload of kombucha, and it tastes pretty good.

The Mad Fermentationist (Mike) said...

Glad it has turned out well for you. I believe tibicos are pretty close to ginger beer plant.

Anonymous said...

I currently have several bottles of GT Dave's Organic Raw Kombucha in the Citrus flavor. I wonder if I can start a SCOBY from a flavored kombucha. Any thoughts?

The Mad Fermentationist (Mike) said...

If it really is raw you shouldn't have a problem. If anyone successfully gets a culture going post the brand name so other people will know which ones work.

Unknown said...

I just started on a bottle of GT Daves Gingeraid Kombucha, and I'll post whether it works or not. But I'd like to know what kind of aseptic technique you use when culturing kombucha from a commercial bottle. I used a rather large mason jar covered w/ a lid, cork, and tube going into a separate jar of water to prevent contamination. Would the size of the jar affect the culture? Also, how do you know when exactly the culture needs more tea and sugar?

The Mad Fermentationist (Mike) said...

Be careful, many of the microbes in Kombucha need oxygen to reproduce, so the way you culture will alter the ratio of microbes.

Much like sourdough you don't have to worry about sanitation, there are enough agressive microbes in there that you don't have to worry about "other" stuff getting in (although fruit flies are a concern). The culture will change and become a house culture over time, but it will stay pretty similar.

Just feed it by taste, if it gets tangy enough for your liking give it some more food to eat until it gets up to the volume you want to produce on a regular basis.

Hope that helps, good luck.

Unknown said...

Ah, ok.. I had read some comment on another website on how dangerous kombucha could be if it got contaminated, so that's why i added the airlock. But now im just going to cover it w/ cloth and see how that goes. So far the gt daves gingeraid kombucha is working great.

Anonymous said...

i'm gonna make my own blog

Tom said...

Hi, Mike,

Sorry to bump such an old post, but I just received a kombucha kit that hadn't been refrigerated. Do you think I can revive the culture using a sanitized tea-and-sugar mixture similar to a yeast starter? If so, how would I know it's fermenting - does it krausen like yeast would?

The Mad Fermentationist (Mike) said...

Shouldn't be a problem. I would just make a small batch of kombucha, add some of the liquid that came with the mother as well. When the culture is working it floats, but it will not make a krausen. You can then step it up to get to whatever size batch you are interested in doing.

Good luck!

Unknown said...

First off, love following the site. My question is, when you have the large "cake," say after a 6 gallon batch is fermented out, do you just dispose of most of the liquid, (since you said it will be too sour), and then just steep a whole crap load of tea (maybe in a mash tun) and mix it with sugar, then pitch the whole volume onto the existing "cake?" If this is correct, how do you know when the batch is finished, is it just by taste preference?

The Mad Fermentationist (Mike) said...

Exactly, the only factor is whether it is sour enough or too sour for your tastes. If the initial batch tastes alright, there is nothing wrong with drinking it (or mixing it with juice or whatever). Subsequent batches can be bottled when they taste ready (although depending on your culture, you'll have to watch out if it is producing more CO2 than you want).