If you’re new to brewing kombucha, or if you’re having trouble with your current batches of home-brewed kombucha, it’s always a good idea to revisit common mistakes you might make and to make sure you follow some simple, best practices to ensure that your kombucha comes out right, and that your kombucha mother stays healthy.
For many of these common mistakes, you won’t see their effects immediately; rather, they affect how well your kombucha brews (and reproduces) over time, making it harder and harder to troubleshoot and frustrating to brew.
Using a Poor Quality SCOBY
The quality of your kombucha depends entirely on the health of your scoby (symbiotic culture of bacteria and yeast). When that scoby is compromised in the way you care for it, or when that scoby is of poor quality because it’s been stored improperly, it’s flimsy or its cultures have been compromised, it will make brewing more difficult, especially for first-time kombucha brewers.
Look for a scoby that is thick, healthy and strong and that comes from a high-quality source that specializes in kombucha and kombucha brewing. The scoby should be thick, robust, and it should come with plenty of starter tea. Whether you buy your scoby, or acquire it from a friend, for best results make sure it hasn’t been stored in the fridge and that it hasn’t come from an original culture that was treated with vinegar.
A robust and healthy scoby, or mother culture, ensures that your kombucha gets off to the best start and that you meet with success from the beginning. For those of you considering starting your kombucha mother from a bottle of commercially brewed kombucha available at your store, read this first.
We recommend Kombucha Kamp as they specialize in producing kombucha mothers and starters for the home brewer and have excellent customer support so that if you have questions about brewing, they’re always there to answer you personally and help you troubleshoot.
Tossing Your SCOBY in the Fridge
The kombucha mother (or scoby) is a collection of living microorganisms, and, as with all organisms, their environment can either support their health and proliferation, or it can damage them. The bacteria and yeast that make up a kombucha mother are sensitive to both excess heat and excess cold. Often new brewers, and even long-time brewers who don’t know otherwise, will store their kombucha mother in the refrigerator until they’re ready to brew.
Over time, the excessive cold of the refrigerator damages the fragile microorganisms within that scoby, weakening it. A scoby that has been stored in the refrigerator is more likely to become contaminated with mold, and to produce weak kombucha or kombucha that doesn’t properly culture.
Instead, create a scoby hotel to store your excess kombucha mothers and babies. The Big Book of Kombucha offers some excellent tips on what to do if you’ve already stored your scoby in the fridge in addition to other troubleshooting tips and guidance on making kombucha.
Rinsing Your SCOBY
Novice brewers will sometimes rinse their scoby before adding it to sweet tea to brew kombucha, much as you might rinse a handful of cherry tomatoes before tossing them into a salad. A scoby, by contrast, doesn’t need rinsing. You’ll rinse away some of the microbes that are responsible for helping your sweet tea to transform into kombucha, so, as a best practice, move your scoby directly from one batch of kombucha to the next, with minimal handling and it’ll do just fine. If you drop it, you might consider giving it a rinse to remove excess debris it may have picked up on the ground.
Storing Your Kombucha in Direct Sunlight
Just as storing your kombucha mother in the fridge can weaken the cultures over time, so can brewing your kombucha in direct sunlight. As a rule, you should avoid fermenting or culturing anything within direct sunlight as the temperatures are inconsistent and can rise, creating an inhospitable environment for the very bacteria and yeast you’re trying to help grow. Instead, consider brewing out of direct sunlight. Indirect light is fine, as is a dark cupboard.
Adding Vinegar to Your Brew
From time to time, you see recommendations to add apple cider vinegar to your first batch of kombucha. Adding vinegar the first time you brew kombucha is intended to acidify the sweet tea, and, theoretically, help the kombucha to take root and get started. The truth is that you never need to add vinegar to your kombucha; rather, you need a SCOBY and a starter tea which should come with any kombucha mother that you purchase or that is given to you.
Adding vinegar, particularly apple cider vinegar, can introduce vinegar eels – a small nematode that thrives in acidic environments and feeds off of kombucha mothers. While harmless to humans, they can weaken your kombucha scoby and damage it (and its ability to brew kombucha) over time. Vinegar eels are a very common blight in the vinegar industry, and particularly so for apple cider vinegar. The only way to eradicate them is to use sulfur dioxide or pasteurization (source), neither of which you want to use in your brewing.
Vinegar eels are another reason to make sure you’re using a high-quality kombucha mother from a reputable sources (like this one), as unsuspecting home brewers may have used contaminated vinegar in their initial brews and then passed on resulting mothers to their friends, unaware that they’re also passing on vinegar eels, too.
Using Weak Starter Tea
The kombucha SCOBY and kombucha starter tea work together to transform sweet tea into kombucha. Young kombucha tea, less than six days old, isn’t sufficiently inocculated with enough bacteria and yeast to support the continued brewing of kombucha. So if you repeatedly brew kombucha tea with weak starter tea, instead of mature starter tea (7+ days old, bright and tart), over time your kombucha may become weaker and weaker.
Oversteeping Your Tea
When you steep black tea in hot water, you release tannins and other components of the tea into the water. Properly steeped and well-brewed, tea elicits extraordinary flavor, but when that tea is oversteeped it can become very bitter and unpleasant. Oversteeping also leads to super strong, assertive kombucha with unpleasant bitter overtones. Moreover, regularly using oversteeped tea – like tea infused overnight, can weaken the coby over time.
Instead, for best flavor, consider steeping tea according to recommended brew times.
Adding Flavors to Your First Ferment
Kombucha flavored with citrus, herbs, fruits, herbs and spices is delightful, especially when you take the time to concoct your own favorite flavor profiles, but one of the biggest mistakes new brewers make is adding flavorings to the initial batch of kombucha. Brewing flavored and fizzy kombucha is a two-step process with an initial period of fermentation in an open vessel with strictly tea and sweetener followed by a second, shorter period of fermentation in a sealed bottle with brewed kombucha tea and flavorings.
Herbs and spices, as well as fruits can compromise the growth of the SCOBY, especially over time either by contaminating the SCOBY with mold spores, as in the case of berries, or by damaging the kombucha mother with their natural antimicrobial properties. Your best practice is to keep flavorings for the second ferment, and if you’d like to experiment with flavoring the first ferment, remember to always keep a kombucha mother brewing in just sweetened black tea in case you have to start over.
Not Stirring Your Kombucha Tea
If you’ve ever opened up your bottles of kombucha tea after the secondary ferment only to find that some of them practically explode with fizz while others are flat, you probably felt pretty bewildered and a little frustrated. The fizziness of kombucha largely, though not entirely, comes from the action of naturally occurring yeast. The yeast tend to fall toward the bottom of the brewing vessel as the kombucha tea cultures. So if you pour kombucha tea directly from your brewing vessel into your bottles, then that yeast will not be evenly distributed. As a result, some bottles will be super fizzy and others flat.
As a solution, after you’ve removed the kombucha mother and some starter tea for your next batch, consider stirring the remaining tea to evenly distribute the yeast and bacteria before pouring them into your bottles for the second ferment. You’ll have much more even results.
Using a Noncaloric Sweetener
Many of you are likely looking to cut down on your sugar intake, or cut it out completely, so you might consider brewing with a noncaloric sweetener such as stevia (read more about stevia here), xylitol, erythritol, or another noncaloric sweetener. It sounds good in theory: you’re still brewing kombucha, but without all the sugar, right?
Here’s the problem, the bacteria and yeast that make up the kombucha mother and actually brew your kombucha tea need the calories that come from sugar in order to thrive and do their work. Trying to substitute a noncaloric sweetener for sugar effectively starves those microbes, and doesn’t support the fermentation process needed to transform tea into kombucha. Instead, use a caloric sweetener like white sugar to brew your tea, and if you’re still concerned, consider avoiding kombucha and choosing other fermented foods, like homemade sauerkraut or sour pickles, or beverages like Beet Kvass instead, none of which require added sweeteners.
Resources for Brewing Better Kombucha
If you want to take your kombucha brewing to the next level, or if you want to just get started on the right foot, make sure to check out the Big Book of Kombucha, by Hannah Crum and Alex LaGory. It’s a fascinating book that goes into the history and science of kombucha brewing while also providing easy recipes, simple tutorials, flavoring guides and great resources on trouble shooting your brew.
They’re also the folks behind Kombucha Kamp, which is where I buy my supplies for brewing kombucha and jun tea (kombucha’s lighter cousin).
Nora says
I used Manuka honey and green tea
The color was lighter after one week
The Scooby at bottom
Some thin layer or dark black soft gel like been formed at the top of my Jar
Have I killed it ? And if yes how can I dispose it, compost or normal bin?
Diomy says
Hi, it sounds like you are making Jun tea. What they dont tell you is that the cultivated yeast react better to the sweetener they are first raised on. So a Jun tea scoby will be happier with honey than sugar and vice versa. It may have also fallen if it was disturbed. It doesn’t mean it wasnt working, it just means its harder to see if it did work. You also really don’t need a scoby to make it. All you need is actually enough of the starter tea. Whatever starter you use, just make sure you stick to the sugar it was first raised on. This is a little late, but I hope it helps.
barbaraaa says
Hello, I have got a Scooby from a friend, it looks pretty healthy. But for mistake I have toss all the liquid, I have kept just the Scooby and added a new tea-water-sugar and vinegar mixture. Now I am reading that actually vinegar is bad for the Scooby. How can I fix the situation? Should I toss again all the liquid and put the Scooby in a new mixture of tea-water-sugar? Is the Scooby growing again? would Scooby survive only with sugar and without tea?
RebeccaL says
Help, I received a very lovely SCOBY today from a friend but it didn’t come with any starter tea. I read to add a cup of distilled vinegar to the half gallon sweet tea mix.
I put the SCOBY in today.
Should I make a new batch of sweet tea and move the scoby? Now I’m worried I am ruing it.
Thank you!
magdalena says
Hello hello 🙂
thank you for creating this supportive source of information 😀
I have a question, I just started a new batch- I had a tiny soby and didn’t have much starter liquid on hand, it seems to be going ok so far (smell and looks) it’s a 4th day. Do you think it would be ok to add more starter mid-brew? thanks so much!
Jordan says
Hello! hopefully this reaches the right person! I just started the Kombucha Journey, I bought a Dehydrated SCOBY from my local health food store, the instructions said to add distilled white vinegar since I assume I’m growing the SCOBY from a rehydration. I added less Vinegar than prescribed but my concern is the SCOBY not culturing? how will I know if it works properly? any help is greatly appreciated thank you!
Jenny says
Hi Jordan, I only recommend using a fresh LIVE SCOBY as dried versions yield very poor results, in my experience.
Milt says
I had a batch go mouldy, I’ve already put the Scooby in a hotel…should I throw it out? Could it infect other scoby s in the hotel?
Jenny says
I would throw it out, and I’d watch your other SCOBYs carefully.
jonny says
hey there, ive made kombucha a few times in my life and feel pretty secure with my method. the one spot im having an issue with is a reactivation of a previously hibernated scabby. i let it sit in a regular mix for about 6 weeks. ive tried to make a new batch and its going quite slow (16 days). its made a new scoby already bt isnt tart enough taste wise. any ideas? thanks for your time. jonny
Donna says
Hi! Happy Thanksgiving! I have a quick question:). I make Kombucha regularly but I completely forgot to add the 1 cup of Kombucha liquid in with the scoby and 1 cup of sugar. I noticed a scoby was not forming at the top as usual and it is the 7th day of the 1st fermination. Is it ok to add the liquid now?
Jenny says
It’s too late.
Margie says
Question. Friend dropped her scoby in soapy water. Can it be rinsed and used? I told her to rinse it with water and then with vinegar..
Jenny says
Her best bet is to rinse it gently in water and return it to a good brew. She should not rinse it with vinegar.
Corey Mitchell says
Jenny,
Thanks for the post!
Question for you. I’ve had 10-12 successful batches of Kombucha, but recently the flavor is off and there’s a slightly odd smell. My first thought was that it was a somewhat musty smell/taste. It’s just strange.
My theories:
Moldy scoby? I inspected my scoby hotel and can’t find any indication of mold anywhere.
The hotel is quite vinegary, so perhaps it’s too vinegary to use as a starter liquid?
It started around the time I started using pickle jars to brew, maybe there’s something left over in them that contaminated my culture? I did wash them thoroughly with soap and hot water, though.
Bad batch of tea leaves? They smell normal, though.
Too much yeast? I ran my starter through filters in the most recent batch and wiped all the extra yeast from the scoby with the same result.
I’m at a loss. Do you have any idea what could be happening?
Bev says
I see that your method uses black tea but my Scoby came wth instructions to use green tea bags. Are they interchangeable or can you use black first then use green or white tea. How does the taste compare
Nadine says
After I put the kombucha in the fridge after the 2nd fermentation it has been forming SCOBY s in the refrigerator. What am I doing wrong?
Jenny says
Nothing. It’s normal for a scoby to form in raw kombucha.
Gwen says
Hi Jenny, thanks! If I would shortening the brewing cycle, it would be difficult to keep up. However I could adjust the amount of starter, perhaps I leave too much. How much starter would you use in a 5 liter glass jar?
Janet Cripps says
Hi, I have recently obtained a scoby that was brewed with honey rather than sugar in the tea. I made sugar sweetened tea but the tea doesn’t seem to brewing even though a thin scoby forms on top. Could this scoby only ve honey adapted?
Many thanks,
Janet.
Gwen says
We’ve been making kombucha for a few months now and switched to a continious brewing system. Each week (after 7 days) I take 2.5 liters out and leave about 2 liters in as a starter. I add 2.5 liters of new tea with about 145 grams of cane sugar.
We keep finding our Kombucha a too sour. I know shortening the fermentation time, will give a sweeter taste. But I find the weekly process of making the tea, and the 7 day interval great. And I’m afraid it will become too much work and will result in too much Kombucha for us to drink, if I make the fermentation shorter than the 7 days.
Do you have any advice? I have’t measured the PH yet, not sure how to do that.
Jenny says
Hi Gwen, You can measure the PH using PH tape. If your kombucha is too sour, you need to shorten your cycle or culture it at a cooler temperature.
S says
Hi. I’ve been brewing for some time and really have been enjoying it so far. I live in Wisconsin so most of the time I don’t have this issue, but I’m wondering what people do in the summer months with fruit flies? I get them pretty bad in my apartment. I have my scoby in the cupboard in between brews in a mason jar with a breathable cloth sealed with the ring of a mason jar. I’ve read conflicting information about putting the scoby in the fridge. Any suggestions or help would be helpful. Thanks so much!
Jenny says
I would never put a scoby in the fridge – it’s really not good for them, especially in the long run. Using a tightly woven cloth cover should eliminate issues with fruit flies.
Gisele says
Thanks for the get tips!
I am making my 2nd batch and only have 1/4 c. Of white sugar? The recipe I used the first time suggested sterilizing the utensils and hands with vinegar! But the batch came out okay! I hope I haven’t ruined my next batch?
Can one use coconut sugar, well dissolved, or farm honey and if so, would you still use approx. 1 cup?
Thanks
Jenny says
You usually won’t see the effects of vinegar (if any) for many months. Coconut sugar should work fine, and PASTEURIZED honey will work but you may have issues with raw honey.
Crystal says
Great article. Thanks so much for posting. I’m a very unseasoned kombucha maker working on my second batch. The first came out quite nicely 🙂 and I was hoping to have another success. Unfortunately instead of 8 bags of tea, only 7 were used for a gallon of liquid. What kind of problems can this cause?
Billy says
Hey Jenny! Thank you for this list. I was worried there was a whole array of things I was doing wrong when it came to kombucha, but it turns out I wasn’t doing too many! Now I know exactly what not to do when it comes to the next time I make it. Thank you very much!
Cecilia Hofbauer says
I accidentally over steeped my tea, and so my kombucha became pretty bitter, is there any way to fix it, without throwing out the kombucha and starting over, so that it doesnt taste so bitter?
Jenny says
Nope, there’s no way to fix it, but you should still be able to use it as a start for your next batch.
E says
I think I am going to vomit at the thought of vinegar eels! I have never heard of them, but I am glad I did.. I won’t be adding ACV to my kombucha for sure! I will try & find some stronger kombucha starter tea instead. TY!
nicky says
Do I have to wash the container each time after I pour out the kombucha for second ferment? what do i do with the scoby babies ? do i keep that mother for every brew or will the new scoby baby be able to make new batch of kombutcha?
Tyler Black says
I made my first batch and it was perfect, but I accidentally drank too much of it for the next batch and Cultures for Health said you can use vinegar in place of tea from a previous batch. But I just realized that was for a beginning batch. Should I avoid drinking this batch altogether and just use it for the next?
Marnix says
Nice tips! In your article you mention ‘young’ kombucha… but is there somthing wrong with old, say months old..
I’ve stored nu scoby in the same jar as nu brew and now it’s hudge. Can I stille use the scoby and the kombucha?
Jeannie Hinyard says
Thanks so much for these tips. I have been brewing for a little over a year and my second ferments are taking longer and longer and often don’t develop fizz at all. When I first started brewing, it took two days to develop a really nice fizz. Now it is taking 5 – 6 days for the second ferment and often still have no fizz. I have been dipping the tea out of a 2 1/2 gallon jar and that just might be the problem because I never stir it. I also have been letting my tea sit overnight with the teabags in it. I didn’t do either of those things when I first started, so here’s hoping that is my problem and I can get that fizzy second ferment going agin. Thanks for the advice.
Judy Filewich says
My first batch of kombucha has gotten very fizzy in the bottles. They are in the fridge . This batch has been bottled about 2 weeks . It has a head on it like beer . Is it suppose to do that? I’m a new brewer ?
Jenny says
Hi Judy,
Kombucha should be very fizzy in its bottle. That said, if you prefer it less fizzy, take your starter liquid from the top of the brewing vessel instead of from the bottom.
Allison says
I’ve been reading lately that kombucha is high in fluoride due to the fluoride content of tea. I’ve read it several places and I have to say I’m a little shocked. Do you have thoughts on this?
Jenny says
Hi Allison,
Yes, plants uptake minerals and heavy metals from the soil, and this is how our plant foods can be either mineral-rich or mineral-poor. Some plants preferentially take up certain minerals or heavy metals. Tea happens to uptake fluoride. Grapes happen to uptake lead, for what it’s worth. And rice uptakes arsenic.
Some of the fluoride tea uptakes occurs naturally, but most of it comes from man made sources like fertilizers not allowed in organic production, so organic tea typically has less. As the tea plant ages, its accumulation of fluoride increases and its antioxidants decrease, so choosing teas made with young leaves means less fluoride, more antioxidants and, incidentally, less caffeine. So opt for green and white teas if it concerns you.
Studies looking into fluoride in tea have found that cheap (like supermarket teabags) black tea have the most, and high-quality organic teas the least.
Remember, kombucha is brewed with weak tea, not strong, so the amount of fluoride should be inherently lower than, say, a strong cup of tea.
So, if you’re concerned, brew kombucha using water that’s been filtered to remove fluoride using organic green or white tea, and enjoy it in modest amounts, like a few ounces a day, which us how it should be enjoyed in the first place.
Susan James says
Jenny, I have just brewed my second batch of Jun from a scoby I got from a friend. My first batch was fine, but this batch has brown particles in it – I don’t think they’re those eels I read about – they just smeer in my fingers. My friend says they’re not mold – she thinks it’s yeast growths which she’s never grown in hers, but thinks the Jun is safe to drink. It does taste fine, but I am unsure. Your thoughts? Thank you for the time you take answering these questions.
Jenny says
Hi Susan,
If they’re brown strands or globs that smear when you press them, they’re yeast strands and normal to fund in home brewed kombucha.
Lesya says
Please, help-help-help
I took a plump and beautiful kids Scooby from my hotel and made tea for the Kombucha in 4L jar. But my kids Scooby from settling. And they lie on the bottom of the jar the second day.
Please, help-help-help. I love so much my Scooby
Jenny says
Hi Leysa,
There’s no problem if your SCOBY sinks.
Mary says
I made my first batch of Kombucha and immediately made a second batch. I stored my mother and babies in the refrigerator ( following the directions given by the person I got the SCOBY from) because I am going away for 3 weeks. Will I be able to use the SCOBYs after 3 weeks in the fridge? What would happen if I took them out of the refrigerator before I go on vacation?
Jenny says
Hi Mary,
It sounds like the person who gave you the scoby doesn’t know better. I’d imagine that she’s also stored hers in the fridge at some point, meaning that it’s likely that the cultures have already degraded. I would recommend you store them in a scoby hotel (linked above) and hope for the best.
Patti Gregerson says
Thanks so much for the info! I have had trouble with me second ferment not getting fizzy. I’m thinking your suggestion of stirring before bottling is a winner and may be my issue! I’ll give it a try. Great info!
Thanks again!
Michele says
I have seen scobys for sale in my local health food store- can’t remember the name of the company but they are in the fridge- does this mean they would not be the best choice? Thanks
Jenny says
Yes, I would avoid purchasing a refrigerated scoby. Many Brewers aren’t aware of best practices and sell sell subpar or compromised mothers because they don’t know better. Refrigerated mothers are more likely to mold and fail over time leading purchasers to believe they’ve done something wrong when the scoby was compromised long before.
Brei says
Jenny,
I am a long time kombucha brewer. However, the past year or so I have only occasionally brewed. Now I have what looks like a jar of half tea and half Scoby. It’s looking more like a hotel than ready for second ferment. The brew is very acidic and vinegary. Can I make a tasty second ferment from this batch or should we try and do something different with it?
Jean Capozzi says
Hi Jenny –
Can you cut a large SCOBY into small pieces without harming it? What is the best way to keep the extra pieces? TIA.
Jean
Jenny says
Hi Jean,
Yes, you can, and store the pieces in a scoby hotel.
Alison says
I’m not sure why, but a new scoby seems to be growing in my bottled kombucha! I allowed my first batch to ferment with the scoby for 7 days, but then I bottled it with ginger and turmeric in separate bottles (without the scoby). Did I accidentally add some of my scoby into the bottles?
Jenny says
Hi Alison,
Your kombucha is a source of live, active bacteria and yeasts – the very same ones that make up the SCOBY that made your brew. As they contain all those components, they will sometimes form baby SCOBYs in the bottled tea. Especially if it’s a very strong culture, like yours seems to be.
Sunny says
I started with a beautiful scoby, which is thick and healthy. If I let mine brew too long and made vinegar, do I have to be concerned about vinegar eels? I made a wonderful booch after the vinegar (which I bottled and kept). Have I damaged my scoby?
Jenny says
Hi Sunny, As long as you got your Scoby from a reputable source and as long as you never added vinegar (or cleaned your brewing vessel with ACV), you shouldn’t have to worry about vinegar eels no matter how long you brew it.