Fermentation Basics – Kombucha


If you have been in the US since the 1990s, you’ve likely heard about the outstanding health benefits of kombucha.  I can’t speak to the miracle claims from personal experience, except to tell you that if you are experiencing a post-Thanksgiving food or drink hangover, skip the self-recrimination and go for a gigantic slug of the big K.  I can feel myself getting my soul back as it moves through my system.  And there is actual science that says kombucha supports liver function.

Making kombucha is super simple once you get the key element: the SCOBY.  SCOBY is an acronym for Symbiotic Community of Bacteria and Yeast (cute, right?) and it is sometimes called the mother or the mushroom.   The best place to get your own scoby is from a friend or fellow fermenter.  SCOBYs auto-reproduce in the kombucha-making process, so anyone who regularly makes kombucha will probably have an extra or two laying around.  The SCOBY plus a bit of kombucha from the last batch will get you started.  I got my most recent SCOBY from Allyson Kramer, the amazing blogger and photographer at Manifest Vegan.  She is also the author of the cookbook I’ve been using to make my friends and family crave gluten-free, vegan food for the past several months, Great Gluten-Free Vegan Eats.  (Seriously, I made dudes watching football unknowingly devour gluten-free vegan things and ask for more.)  I can honestly say this is the best SCOBY I’ve ever had, it makes babies like a (vegan?) mofo and produces the most delicious kombucha I’ve ever had, bar none.  I used to be a sometimes ‘boocher, but with this SCOBY, I’ve started experimenting with constant fermentation and making a batch every week.

Once you have your SCOBY and your starter kombucha, you are ready to go!  Don’t freak out about the sugar. It gets partially or entirely converted (depending on how long you let your big K ferment) and your guts will thank you for giving them all the healing bacteria and the glucaric acid which may help the liver function more efficiently (see previous hangover comments) and may have anti-carcinogenic properties.

Makes 1 gallon of kombucha.  You can adjust batch size to your needs/projected hangover level.

A note on carbonation:  The best way to get super bubbly ‘booch is to do secondary fermentation. Your kombucha is done when the sweet/sour level is where you like it, not when it’s bubbly.  That said, in the warmer months, your bubbles may be vigorous in the first round of fermentation.  See after the recipe for the simple secondary fermentation how-to.

Recipe after the jump.

Simple Kombucha


12 c water

2 T  tea (no tisanes, must be from the camellia sinesis plant: plain black, green or white. No flavored tea!  The oils on, say, an earl grey could interfere with fermentation and/or damage your SCOBY.)

3/4-1 c sugar or other natural sweetener (honey has antibacterial properties and should only be used with a spare SCOBY in case it kills or hurts it)


2 c starter kombucha

A wooden or plastic spoon

A large, non-metallic container in which to ferment.  Metal will damage your SCOBY.


Heat your water.  Add in the sugar and stir until it’s dissolved.  Put your tea in and let the mixture cool to room temperature. You really don’t want it hot or even warm, since that could mean the death of the little life forms that make up your SCOBY.

The tea is too damn hot (so don’t add your SCOBY yet)!

Once it’s totally room temp, strain out your tea or remove your tea bags.  Pour the sweetened, cooled tea into your kombucha making container (glass or ceramic with NO metal parts) and add your starter tea and scoby.  Cover it with a cloth or coffee filter and secure it with a rubber band.  You want the air-yeast™ getting in there and the gases released in the fermentation process to escape, but you don’t want flies in it because they are disgusting.

That’s it!  Leave it a few (3-8)* days, depending on temperature and your sweetness preference, undisturbed and away from direct sunlight, and you’ll end up with kombucha.  The longer it ferments, the more vinegary and less sweet it will be.  You can definitely taste it along the way to see what sweetness level is a good stopping point for you.

Strain out your SCOBY using a non-metallic mesh strainer and start a new batch.


Primary and secondary (Fermentation) live together in perfect harmony

A few tips:

The white film on the top is a good thing!  It means things are working and your scoby is making a baby.  It will thicken and become a whole other scoby that you can then pay forward to a friend.

If your existing scoby gets some streaky things hanging off of it, that’s cool!  Just some extra slimy yeast that is created in the process.  I personally do not enjoy drinking it, so I strain it out before drinking and toss it in the compost pile.

My current SCOBY makes an enormously effervescent kombucha (yum!) but in the past, I’ve had to do a little secondary fermentation to get the bubbliness rocking.  How you do this: pour your finished tea (sans SCOBY) into a container that more or less seals (a plastic 2-liter, a ball jar, a flip top bottle as above, etc).  Seal it.  Leave it for a few days.  Done.  This is also a great time to flavor your kombucha by adding ginger chunks, dried fruit, juice, etc. if you are into that.  Remember that you DO NOT want to add anything to the tea when the SCOBY is still in it.

IF you do secondary fermentation in a glass jar, make sure you are checking it daily and DO NOT leave it more than a couple of days.  Your jar could explode.  This is a serious risk.  It has never happened to me, but be aware that if you forget about it, bad things can happen.

*5-8 is the time period that I have found works best with my SCOBY in my house, in cold weather in a cold house, I sometimes leave it for 2 weeks.  You might like it more sour or fermentation might occur more slowly in your environment.  According to Cultures For Health, you do not want to let it ferment longer than 3 weeks, because your SCOBY could starve.  Other than that, it’s done when it tastes done to you!

DUE TO OVERWHELMING DEMAND (by which I mean requests for cultures that became utterly overwhelming) I no longer ship individual cultures or meet up with individuals to share cultures. Every so often, when I have too many cultures around the house, I send out an announcement and set up shop at a cafe, where cultures are bagged up and ready to share.  They can be taken, self-serve style, on a first-come, first-served basis.  If you’d like to be informed about those times, please sign up for my mailing list under “Classes and Events” or follow me on Facebook or Twitter.

Basics Ferment Probiotic Vegan Vegetarian


  1. Sarah says:

    Thank you so much for sharing all this info. I was wondering if you would be able to share some SCOBY with me? I want to start my first batch!! I’m a student at UPenn; please let me know if you’d like to arrange something!!

    • Amanda says:

      Hi Sarah,

      Absolutely! I’m out of state until next week. Shoot me an email when I’m back and we can definitely arrange something. I live in the Italian Market area.

    • Amanda says:

      Hi Zoey,

      I generally have lots of extras. Anyone who’s willing to pick them up near the Italian Market (weekends) or in Old City (during late business hours) is welcome to them. I’m not in town at the moment, though!

  2. Jiyeon Kim says:

    Hi! I love your blog! That’s so awesome that you make kimchi! I’m korean and I actually just made a big jar of kimchi too!

    I’m hoping to make kombucha and was wondering you had extra scoby? My mom and I used to make kombucha back in Korea.. and I miss kombucha so soooo much! Please let me know. You and your blog is awesome!!

  3. Yves Guyon says:

    I took the soda making class with you through greensgrow and loved it!
    My batch of kombucha got moldy at the top overnight (i think its day 5) What do I do? Is it a lost cause? Merci!

    • Amanda says:

      Hi Yves,

      Thanks for the kind words! Much appreciated! The kombucha grey/white thing is almost definitely a new SCOBY forming. You can let it get thick enough that it’s easily removable, or you can just ignore its existence and continue the kombucha-making cycle. You’ll get a new SCOBY with just about every batch. Ravie de vous connaître. N’hésitez pas à me poser toutes vos questions fermentation!

  4. Hi Amanda,
    My kombucha never gets carbonated (and my ginger bug definitely does, way too much!). I got my scoby from a guy on kijiji (canadian equivalent of craigslist). Is it possible that my scoby is really just a vinegar mother? I’ve tried so many things to get it to carbonate and none have worked. Thoughts?

    • Amanda says:

      Hi Jon,

      I’ve actually fermented kombucha with a vinegar mother and gotten really bubbly “kombucha,” so I don’t think that is the issue. What have you tried to get carbonation going?
      Top things:
      Warmer primary fermentation
      Secondary Fermentation with fruit (berries especially add bubbles)
      After secondary, add a large pinch of sugar before bottling in a truly airtight container.

      I will also tell you that I never had particular luck (it was inconsistent) with carbonation until I got the SCOBY I use now (which I got from a friend, but she got it from Kombucha Brooklyn). How is the health of your SCOBY in general? Does it reproduce every batch, is it thick? Lots of yeast strands or mostly white? You might also want to try rebalancing the tea/sugar/water/starter tea ratio you use. I’ve had a lot of success with the ratios from this Cultures for Health Chart. It might be worth getting another SCOBY, but with the winter coming, you’re going to get less carbonation in general (in my experience). I hope that helps!


  5. Well, I think there’s yeast, because there’s definitely brown things hanging down from the scoby. It seems more or less healthy, it floats and seems to grow from batch to batch. I’ve added sugar to the bottles and use swing tops. It’s definitely warm in my house too. I’m wondering if I’ve been making the tea too strong, I’ll try the ratios from that link. I’ll keep tweaking things but may eventually need to try a new scoby.

    • Amanda says:

      No problem! I don’t want to be the one to tell people to buy stuff, but I really did have a better experience with this SCOBY than I have in the past. The continuous brew also definitely helps with carbonation. Might be worth a go! Good luck and let me know if you ever crack the code!

  6. Nicole Giusti says:

    Hi Amanda! Thank you for your very informative post. I was looking for classes to start learning how to make kombucha in the Philadelphia area, but if you had an extra SCOBY I was wondering if you wouldn’t mind donating it to me! I live just a few blocks south of the Italian market, and would not mind picking up from you. Please let me know!

    All the best,


  7. Ali says:

    Thanks for the great blog post. I just moved to Philadelphia this fall from Santa Cruz, CA where I brewed kombucha in the past. I am trying to find a SCOBY I can buy off someone locally. If you have one, please email me and I can pick it up! Thanks.

  8. Barty says:

    How do you: make sure the tea doesn’t explode during the secondary fermenting process/stop the fermentation during the secondary phase. In other words… Do you know it is ready by opening it and tasting it? Say it is done… do you ensure it doesn’t explode by not keeping it in a sealed jar or…?

    • Amanda says:

      Hi Barty,

      There are a few ways I make sure my ‘booch doesn’t explode:
      1. Use plastic bottles, or at least have one plastic bottle. When the sides are hard, it is fully carbonated and should go in the fridge.
      2. Don’t do secondary in a sealed container. A mason jar works fine. You can then bottle it after straining out whatever fruit/herbs/etc. you’ve added during secondary, if you are concerned with carbonation.
      3. Do secondary for a longer period of time in the fridge. (Some of the yeasts may die off in a cold fridge so you have to decide if this is right for you).

      I hope that helps!


  9. Kyler Thomas says:

    This sounds amazing and I’d really like to give homemade kombucha a shot. Do you happen to have an extra SCOBY that is in need of a loving, new home? I’m a med student in Philly (Society Hill area).

    Best wishes,


    • Amanda says:

      Hi Kyler,

      I would love to offer you a SCOBY, but I’m going to be out of the SCOBY sharing business until at least May, I’m sorry to say! I have two larger classes between now and then and for both, participants will get a SCOBY to take home, which leaves me in production,rather than sharing, mode.

      You might try asking on the Philadelphia Urban Farming Network (PUFN) group. Lots of kombucha-types get the messages and many are willing to share SCOBYs!

    • Amanda says:

      Hi Kristin,

      I would love to offer you a SCOBY, but I’m going to be out of the SCOBY sharing business until at least May, I’m sorry to say! I have two larger classes between now and then and for both, participants will get a SCOBY to take home. That means I won’t have any extras to share.

      You might try asking on the Philadelphia Urban Farming Network (PUFN) group. Lots of kombucha-types get the messages and many are willing to share SCOBYs!

  10. Alina says:

    Hi Amanda!
    I am so happy I found you and your scoby!
    In Russian it’s called a tea mushroom, and my mom used to have one but she had too many fruit flies because of it so she got rid of it. This was years ago. In the past year and a half I’ve had many digestive problems and learned that kombucha can really help me due to it’s probiotic qualities and many healthy gut bacteria. I am 95% recovered from gastritis and but have IBS, which I am trying to cure. I was really sick and had no hope, and doctors didn’t do much. With research and experimentation with things I found I am recovering. Please please share your scoby with me. You will save my life. :) What is your email? My phone number is [deleted]. I will be more than happy to pick it up. I’m close to center city, Philadelphia.

    • Amanda says:

      Hi Alina,

      I’m so glad to hear you’re on the mend!
      I would love to offer you a SCOBY, but I’m going to be out of the SCOBY sharing business until at least May, I’m sorry to say! I have two larger classes between now and then and for both, participants will get a SCOBY to take home. That means I won’t have any extras to share.

      You might try asking on the Philadelphia Urban Farming Network (PUFN) group. Lots of kombucha-types get the messages and many are willing to share SCOBYs! You can also buy them from Kombucha Brooklyn online or Philly Homebrew Outlet in Nolibs.

      Good luck with your healing journey!

  11. Mariel says:

    Hi Amanda,

    This is a wonderful blog! Is there any chance you still have scobys to share? I want to get one as a birthday gift for my sister, who is revved and ready to start making her own kombucha. I live pretty close to the Italian Market so I’d be more than happy to pick it up.


  12. Taylor R says:

    Hey Amanda!

    I live in Philadelphia and would be very interested in getting a SCOBY from you. I live in Manayunk and can get into your area very easily. Would it be possible for the two of us to meet up?

    Thank you for the helpful article!

  13. Nina Rose says:

    Hi Amanda!

    Great blog! I’m looking to try to make Kombucha for the first time and wondering if you have any extra SCOBY you are able to donate. I live in the Italian Market area.

    Thanks :)

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