How to Tell if Your Kombucha SCOBY is Healthy
If you have had any exposure what so ever to SCOBYs, then you will know that they are weird looking things! I keep my kombucha on the counter (in glass jars) and visitors are generally too grossed out to say anything at all. That’s how attractive and odd SCOBYs usually look.
Because SCOBYs can take on some weird and gross looking appearances, it’s not always easy for a new kombucha brewer to ascertain by looks whether or not their SCOBY is in good health.
So here are some basic guidelines as to what a healthy SCOBY looks like. And what warning signs indicate that something might really be wrong with your culture.
4 Main Signs That Your Culture is Healthy
If your culture is displaying these signs then it is quite likely that it is in good condition.
A thick culture means that the bacterial part of the SCOBY is doing well and is able to produce a SCOBY with strong cellulose tissue. However, thin layers are also not necessarily an indication of ill health. If your SCOBY develops lots of thin pancake-like layers quite quickly, this still means that it is healthy. The layers are just not bound together as with a SCOBY which gets super thick.
A culture which has a rubber-like consistency also indicates good bacterial health. Cultures which are softer and more slimy and soft feeling (especially when thick) can show that the bacteria are not producing as high a quality cellulose structure. If however this is displayed in an older culture, it does not necessarily mean that your strain of kombucha microbes is compromised. It probably just indicates that the SCOBY layer in question is old and does not have a high level of vitality anymore.
#3 Fast Growing
A SCOBY which thickens or creates new layers (i.e. a Baby forms at the top) quickly is usually in good health and the microbes are going strong. This, however, is also not a hard and fast rule, as temperatures can play a role in how quickly the SCOBY grows.
#4 Good Kombucha
And of course the ultimate indication of a healthy SCOBY is that it makes good kombucha! If your SCOBY is taking a long time to ferment the tea it is in this can mean that it is lacking in vitality or is compromised in some way. On the other hand, a culture which ferments the tea it is in too quickly is also an indication of a problem. This is usually caused not so much by a lack of vitality, but an imbalance between the bacteria and yeasts. The yeasts have the upper hand and are throwing the fermentation process off. Resulting in prematurely sour kombucha.
SCOBY Characteristics Which Look Wierd – But are OK
Below are some of the characteristics which SCOBYs can display, which while they can look awful – do not mean that there is anything amiss with your culture.
Lumps and Bumps
Every now and again it is not uncommon for a SCOBY to develop bumps on its surface. This looks super odd, and one immediately thinks that something is wrong. There is nothing to worry about. The bumps usually disappear within a brew cycle. All they are is an irregularity within the structure of the cellulose housing of the SCOBY. Some brewers believe that this is usually brought on by a change in tea type.
Dark Spots on SCOBY
These are simply yeast spots and perfectly fine. Often yeast bits / spots can form on a developing SCOBY or may accumulate as splotches on older SCOBYs. Again, nothing to worry about here.
White Splotches on Surface of New Brew
One of the most common pictures sent to me by panicking (inexperienced) Kombucha brewers are images of white splotches on the top of a newly fermenting kombucha. These can be, at first glance, confused with mold.
But they are not. They are simply a newly forming SCOBY which is formed in little circular splotches at the top of the container. These might be a millimeter in circumference to several inches.
Unlike mold, these will be SLIMY and not fuzzy or dry. In 5-7 days, they will meld into a single SCOBY.
It is common for SCOBYs to take on a light beige color. This can even deepen to a disturbing shade of brown! However yucky this might look, nothing is wrong. The discoloration is a result of staining from the tea medium. As proof, green tea usually produces beautiful pearly white SCOBYs!
What dark SCOBYs can indicate is that the culture has been fermenting tea for quite some time. If that is the case, it might be a good point at which to swap it out for a younger and more energetic recruit. Or, if it has gotten thicker and thicker, you can simply peel off the bottom layers. This will mean that you are left with the youngest part of the culture to ferment with. For guidelines on how to do this, take a look at these posts How To Divide A SCOBY (Remove Baby from Mother) and How To Cut A SCOBY In Half.
Read the general difference between White vs Brown vs Yellow SCOBYS.
When making kombucha for a little bit, one can expect to encounter brown strings. These can be free floating or loosely attached to the SCOBY. These are the yeast colonies, and far from being bad – we need them! However, too much of these strings can again indicate a yeast dominated ferment. But no stress, all you need to do is pull a couple off and discard.
Bubbles Under Forming SCOBY
Sometimes you get little bubble pockets under your forming SCOBY. This is perfectly fine and while you may not get the classical white, round SCOBY, you still have a perfectly healthy culture. Don’t freak out!
It’s simply pockets of gas (from the fermentation) trapped under the surface.
A Sunken SCOBY
Usually, SCOBYs tend to hang out on the surface of the kombucha which they are busy fermenting. Sometimes, however they can sink right down to the bottom, or hang out somewhere in between. If this happens, there is nothing to worry about. Your kombucha will continue to ferment. The SCOBY will most probably make its way back up to the surface at some point, or a new one will form there.
If You See This – You Must Throw Away Your SCOBY
As you can see there is a host of SCOBY oddities which in no way mean that there is anything wrong with your culture. However there are a couple of signs which do spell trouble. If you see either of these – then you will need to throw out your culture completely.
Mold spells the end for SCOBYs. There are some SCOBY moves which look to a quick glance like mold. However real mold is quite easy to identify if you take a close up inspection. It is characterized by a furry look, like a small carpet of upstanding hairs. Another definitive feature is that it is always dry. It will not develop under the surface of the tea, and it will not look moist or slimy.
However real mold is quite easy to identify if you take a close up inspection. It is characterized by a furry look, like a small carpet of upstanding hairs.
Another definitive feature is that it is always dry. It will not develop under the surface of the tea, and it will not look moist or slimy.
Mold is usually white, but can also be brown or black or greenish. Don’t confuse mold spots with yeast or with a brand newly forming SCOBY (less than 4-5 days) which can take the appearance of white splotches on the surface of the liquid that will form together into a single layer. These white splotches are slimy, not dry.
If you have Mold, here’s what to do.
It’s possible (but rare) that you could have a vinegar eel contamination. These are actually not eels but little nematodes that are often found in Apple Cider Vinegar (and vinegar distillations). It’s possible you can get a contamination in your Kombucha. While you won’t get sick from these, the worms look pretty disgusting.
Fruit/Vinegar Fly Infestation
Fruit/vinegar flies can be incredibly attracted to kombucha. So much so that they like to lay their eggs in the surface of the SCOBY! If the covering for your kombucha is tightly secured, then there shouldn’t be anything to worry about. If however, there is a little gap and they have gotten in, the chances are eggs have been laid. So if you find a few of these critters fluttering about in the kombucha bottle, this means the end. The eggs are microscopic in size, so to be totally rid of them you will have to chuck out the whole batch of kombucha, SCOBY and all.
Here’s a trick to make a fruit fly trap out of booch to keep the fruit flies away.
The best course of action in both of these cases is, as stated, to chuck out the whole brew and the SCOBY. Then sterilize all of your vessels and brewing items with hot water and vinegar.
As you can see, you probably have nothing to worry about. SCOBYs do weird things and generally look strange. Unless of course, you have got a supermodel SCOBY on your hands which lives in green tea and is at a pearly level of perfection. : )
On the flip side however, if you realize that you have mold on your SCOBY, or that it has been contaminated by fruit flies, then it is time to take action.
For more information about troubleshooting your SCOBY with some of our related articles: