Detect mold in Kombucha and successfully prevent

green mold, blue mold, kombucha, mold

A warm “Hello” to all fermentation enthusiasts:-)

We are repeatedly asked by phone, email, but also through our numerous blog posts, how you can actually tell whether the new kombucha batch was just a new, vital baby kombucha, or whether mold has actually crept in with it. Especially those of you who are making kombucha yourself for the first time are sometimes very unsettled. But rightly so, because anyone who has not dealt with the topic of fermentation and in particular kombucha fermentation before, will be confronted with images during this extraordinary process that are difficult to classify. But first of all, real mold is really only in the greatest exceptional case.

Probably some of you ordered a kombucha starter package online a week or two ago and immediately started preparing kombucha. It survived the transport in the package to your home without any problems and most likely looked something like this. Smooth and strong with a pleasant, sour, yeasty odor:

Organic kombucha, vital culture, buy online, mold-free

This is what a fresh, vital Kombucha culture looks like without mold.

Well, and now something indefinable is forming, at least indefinable up to now.

For an initial assessment of the situation, please check the following:

• Has your Kombucha Scoby grown or has a new fungal skin or a thin membrane already formed on the tea surface?
• Does your kombucha mixture smell fresh, yeasty and slightly sour?
• Is the fungus free from green, black, white or blue mold and is it neither dusty nor hairy or furry?

If all of these questions can be answered with a clear “YES”, things are looking pretty good:-)

What does a vital Kombucha look like without mold?

We will now show you what a vital and healthy Kombucha tea fungus without mold looks like:

de] Kombucha, Schimmelfrei, Hefe-SchlierenKombucha, mold-free, yeast streaks

A thin Kombucha mushroom with lots of yeast streaks has developed here.

Here you can see a freshly developed Kombucha culture. It’s not as nice as the one you bought online. But like us humans, it comes down to the inner values. It doesn’t really matter what he looks like. Unless, of course, it really is mold. With a healthy Kombucha SCOBY (Symbiotic Culture Of Bacteria and Yeasts), all that matters now is the bacteria and yeast that make up this little miracle. The resulting Kombucha skin is quite light and very thin. Quite simply because it is only about ten days old. You can see small bubbles on the side. This is completely normal, because carbonic acid is formed during the fermentation process. This wants to rise, but remains attached to the kombucha and is sometimes visible to us. In addition, you can see bulging brown spots on the scoby. The bulge is caused by the fact that air bubbles, which you can also see on the glass wall, want to rise, exert pressure in the middle and, among other things, push up the yeast streaks that have formed. With this Kombucha, there is the all-clear with regard to mold growth.

Kombucha, mold-free, bulges, bubbles

This is what a fresh, vital Kombucha culture looks like without mold.

This specimen is also an impeccable Kombucha culture. It is not that nice and smooth and has a lot of bulges. But everything we see is part of a normal, vital tea mushroom. In the picture at the bottom left you can see how the different layers are formed and how they fold over due to the tapering of the glass. At this point, of course, we have to add that this is a several weeks old batch. If your homemade kombucha batch looks like this after a while, everything is fine.

Young kombucha mushroom, no visible mold

Here an active, young, thin kombucha mushroom has arisen.

Despite the same ingredients, a vital Kombucha tea mushroom has been created here, that looks completely different.

Perhaps reading Kombucha Scoby will soon establish itself alongside reading coffee grounds 😉 If you look at it long enough, you can discover beautiful shapes like clouds.

Also this Kombucha culture is in the best of health. The very thin spots indicate that the batch is still relatively young or that the fermentation took place at a low temperature.

The same ingredients, the same procedure but different manifestations – the main thing is mold-free!

Mold-free, kombucha, no mold, edible

This Kombucha culture is vital and has no signs of mold.

This kombucha has a really nice texture and extraordinary grain. If properly packaged, it could go on sale without any problems. All the shapes and grains are the result of normal fermentation and offer no reason for any complaints.

Yeast streaks, kombucha, no mold

This is a kombucha approach that has formed many yeast streaks.

With this homemade Kombucha you can see clearly pronounced yeast streaks. There is definitely no mold to be seen. The sight of such a picture is regularly associated with great uncertainty for the absolute fermentation novice. These yeast streaks are harmless and can easily be consumed with them.

However, if the thought of drinking this “brown slime” offends you too much, that’s no problem either. When filling, simply place a coffee filter in your sieve and the yeast streaks will stick in it. We drink our Kombucha tea completely, without filtering out the yeast. 🙂

Even if we could comment on and evaluate dozens of such beautiful, vital Kombucha cultures, it should have been enough at this point to illustrate mold-free tea mushrooms. We think that you have now got a good impression of what kombucha mushrooms can look like.

How can I recognize Kombucha mold?

Now we come to real Kombucha mold pictures, which clearly document and indicate that something went wrong during the fermentation of your homemade Kombucha and, unfortunately, it was colonized by unwanted microorganisms. In order to illustrate the subject of mold at Kombucha with pictures, we have prepared some Kombucha batches and deliberately provoked the formation of mold.

Kombucha mold pictures:

green mold, blue mold, kombucha, mold

No kombucha fungus has formed here, but green-bluish mold.

The picture above shows very impressively, how mold can grow in a Kombucha batch. Not even a new thin scoby has formed. The dusty, green mold spreads over the entire batch over time. In our opinion, it not only looks unsavory, but can also pose a health risk if consumed. It is important to note at this point, that the mold along with its runners and spores have certainly not only settled on the surface at this point, but will have contaminated the entire kombucha batch. Right next to the green, dusty mold we see bright spots. It looks a bit like curdled milk that is on the surface of the neck and protrudes several centimeters into the kombucha tea. Consumption of this substance along with the full batch is strongly discouraged.

Green mold is the most common of all types of mold in food. In addition to our edible supplies such as bread, fruit and vegetables, it also likes to colonize the potting soil of our beloved potted plants. This type of mold is not to be trifled with, as some are even poisonous. Inhaling the spores can cause irritation of the mucous membranes and respiratory tract as well as headaches.

Organic Kombucha, buy, order online

Not convinced that your own kombucha is really mold-free? If in doubt, be on the safe side and buy a fresh organic quality scoby here online.*

Not convinced that your own kombucha is really mold-free? If in doubt, be on the safe side and buy a fresh scoby in organic quality here online.*

Identify mold, kombucha, mold

Clearly green mold has developed here – be careful!

Unfortunately, this kombucha batch also forms a green mold. However, a thin kombucha skin was created in advance, which was still not strong enough during the fermentation to ward off the formation of mold. Enjoyment is strongly discouraged.

Kombucha, white mold, green mold, mold growth

This kombucha was infested with both green and white mold.

With this batch, a beautiful kombucha had developed and was then also attacked on the edge with green, dusty mold. In the middle of the Kombucha culture, white mold has also established itself. The likely cause of mold formation during this fermentation is that the tea fungus has dried out. Please dispose of such a Kombucha culture along with the complete batch. We strongly advise against making any effort to save scobies that are so infected with mold.

In addition to the green mold, white mold has also settled in this kombucha batch. Even if it is commonly believed that white mold is less dangerous, it can certainly cause respiratory diseases and even allergies. Therefore, caution is advised here too!

Mold, Kombucha, mold growth, recognize, black

This Kombucha culture is completely infested with black mold – do not use this Scoby anymore.

Mold, Kombucha, mold growth, recognize, black

This Kombucha culture is completely infested with black mold – do not use this Scoby anymore.

We are slowly getting all the colors together. This kombucha batch first formed a thin slice of kombucha and then thought about getting moldy. We strongly advise against enjoying this kombucha.

Mold, Kombucha, mold growth, recognize, black

This Kombucha culture is strongly infested with black mold – do not use this Scoby anymore.

At the end there is a picture of a kombucha with black mold, which unfortunately cannot be saved either. Please dispose of cultures with such an infestation immediately.

There are many types of black mold. In general, some varieties are poisonous, very aggressive and robust. The consumption of food contaminated with this type of mold and inhalation of the spores can be harmful to health.

It is fundamentally important that the kombucha batch is not contaminated with foreign germs. Of course, you can’t get it completely sterile. But that is not necessary at all, because the culture itself is very defensive. The kombucha could only surrender, if it had to fight against too many foreign germs, and the pictures above show what the result is. In addition, it is important to create an acidic environment that also contains enough acid. The ratio of preparation liquid to sugared tea has to be right!

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My kombucha forms mold – what to do?

After you have learned how a “good” kombucha can be distinguished from a moldy kombucha, you will now learn, what to look out for in detail, in order to avoid mold formation in the long term and to be able to enjoy every kombucha approach in the future.

Avoid foreign contamination

1. You should wash the fermentation vessel* thoroughly with detergent and then rinse it with hot, clear water. Incidentally, vinegar is also suitable for cleaning. Maybe you still have some homemade vinegar* or even kombucha vinegar left over.

Important: There must be no more detergent residues in the container, as this could damage the kombucha.

2. After the water has boiled, it is advisable to let the tea boil for a few more minutes, to kill any germs that the tea* could bring with it. Incidentally, this also applies, if lower brewing temperatures and brewing times are noted on the instruction leaflet for various types of tea. The choice of tea is also important. Please always use organic varieties without artificial flavors or essential oils, in order not to harm the Kombucha culture.

3. Even the sugar* used could bring along possible germs. We therefore advise you, to dissolve it in hot water at the same time. Goes even faster than in cold water.

4. Do you want to refine your Kombucha drink with fruits, dried fruits* & Co.? You are welcome to do this, but only in the second fermentation. You can find a great recipe for the Kombucha second fermentation here on our blog. The dried fruits and the fruit can also bring germs back into the container, which can damage your kombucha mushroom.

5. Cover your kombucha with a breathable cloth to prevent germs and vinegar flies from entering. Because this is also one of the main reasons for mold growth in your tea fungus.

6. Please take care, not to position the kombucha attachment in the immediate vicinity of real indoor plants. As already described, the plant soil is usually home to a large number of different types of mold. So if there are one or more planters in the house, this could be the cause of mold in Kombucha.

7. Use pure, clean or unpolluted water for your kombucha batch. Water contaminated with germs, chlorine, lead, pesticides etc. can also have a negative impact on the fermentation process. While chlorine, as a volatile gas, is largely broken down during cooking (or is floating around in the kitchen), other substances remain in the water, weaken the culture and possibly lead to mold. If not, these substances are also consumed. You can easily find out the quality of your tap water with a professional drinking water analysis*. Or order a water filter system online here* and play it safe.

Chlorine, pesticides, lead, contaminated water, mold source, mold cause, water analysis, tap water test, buy / order online

Now carry out a water test at home and rule out a source of error.

Make sure there is enough acid

8. Make sure that you always add enough liquid to the vessel to make the environment acidic enough. Unwanted germs can hardly spread or assert themselves against the kombucha symbiosis.

Let the Kombucha symbiosis live and create a pleasant environment

9. Now it is essential to add the Kombucha Scoby to the tea, that has cooled down to room temperature. If the drink is still too warm, this could also damage the tea fungus cultures.

10. Please also make sure that your kombucha does not come into permanent contact with metals. The exception is stainless steel. Small metal clips on tea bags or cutlery can damage the kombucha. We therefore recommend using stainless steel and glass items or if necessary high-quality plastic when handling your Kombucha Scoby.

If you follow all of these tips when using Kombucha, you will almost certainly be mold-free, edible and extremely delicious Kombucha drink received.

EXTRA tip:
If after several attempts mold infestation occurs again and again in your batch, you should take this as an opportunity to delve deeper into research into the causes. If you have really done everything as described and the kombucha is moldy again, it could also be that you have too many mold spores in the air. This could indicate that the mold concentration in your house, your apartment, the kitchen or wherever you make kombucha yourself is increased. The reason for this can be insufficient ventilation, incorrectly performed insulation work or other botched construction.

Mold, kombucha, mold growth, detect, buy mold test online

Now carry out a mold test at home and rule out a source of error.

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Can I still save my Kombucha despite the mold?

Basically, mold does not only affect small, demarcated areas. Under certain circumstances, the mold may have contaminated the tea fungus and the entire batch. Because you cannot find out, at least with the resources available in normal households, to what extent the mold has colonized the culture, it should be disposed of.

How can I remove Kombucha mold?

Of course you can try to remove any mold that has appeared. However, there is a great risk that not all mold spores have been removed and that residues will remain in the kombucha mixture.

Can Kombucha Go Bad?

Yes, Kombucha can go bad or go moldy if something was not optimal during fermentation. If everything goes well, the approach just becomes more and more acidic and forms a new fungal skin over and over again. In the end, both a very sour kombucha vinegar and many kombucha mushrooms were created.

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Greetings send you,

Petra & Stephan

Take a look at this video about Kombucha tea and many others on my YouTube channel …

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  • Reply
    Karina Leidl
    Monday February 6th, 2023 at 04:16 PM

    Hallo Petra,
    Im Zuge meiner allerersten Kombucha Herstellung(hat gut funktioniert, nur die Kohlensäure ist mir noch zu wenig), war ich mir unsicher wie die Oberlfläche des Kombuchas aussehen “darf”.
    Vielen Dank für die aufschlussreiche Seite mitsamt Bildern, das ist wirklich besonders hilfreich für Einsteiger und hilft einem enorm!
    Lieben Gruß,

    • Reply
      Wednesday February 8th, 2023 at 01:10 PM

      Liebe Karina,

      vielen Dank für Deinen lieben Kommentar und Dein Lob.

      Wir freuen uns, dass wir Dir weiterhelfen konnten:-)

      Liebe Grüße

      Stephan & Petra

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