The Kombucha SCOBY Demystified
Sinking, Floating, and Fusing
To the un-initiated, the orientation of the kombucha SCOBY can be a mystifying ponderance. Shouldn't it float at the top? If it sinks, will the brew fail? The answers really are much more of an indifference to chaos than a culture control regimen.
SCOBY has sunken to the bottom of the brew vessel
The mother SCOBY you used to start your new brew should be considered different from the resulting, new SCOBY that grows on the surface of your new brew. Let's call that original the mother, and the new one (that will begin to form on the surface) the baby. When you start your brew, adding the mother to the sweet tea, that original culture may float, at the surface, it may sink, or it may just hover in the middle. Any of these orientations is 100% okay and should not be considered indicative of viability. The mother will potentially fuse together with the baby, too, and that's fine. The SCOBY doesn't have a mind of its own, it's not drowning if it sinks and it's not dangerous if it floats before the baby has a chance to start growing. Much more indicative of brew health is the level of sweetness, which should decrease with time, and acidity, which should increase.
Two original SCOBYs have fused with the new baby, this is normal. No need to call Ellen Ripley.
Most of the time, when I hear that someone's SCOBY has disappeared, the issue is very simple. Just bumping your fermentation vessel while it is brewing is enough to cause the SCOBY to sink below the surface of the tea. So, whereas previously there was a thin baby growing on the surface, it will now have "disappeared." It's very often likely that a little disturbance caused the culture to sink, potentially not being visible in the tea below. But remember, taste your brew throughout the fermentation process so you can tell if it is progressing or not. Nearly 100% of the time it is, and any speculation or fear of failure is unfounded.
Bumped jar scenario; you can see the older SCOBY below a newer layer on the surface; when this happens with a much thinner surface layer, often it can fold up and be imperceptible under the surface.
Your SCOBY after the First Brew
After your first brew, you'll likely have 2 types of culture you will deal with. One will be the original, or mother, culture - this will obviously not always be a single, coherent piece - maybe you picked up 2 pieces of culture from a friend, or got one of our 3-gallon ceramic deluxe kits with 3 SCOBYs, or just used shards of SCOBY from another brew - this culture can all be considered the mother.
Cultures have fused together, mother and baby together in one.
So, you will have the mother and the baby, which will be the new culture that will have formed. Please note as well - new culture will always grow on the surface, and you can't grow kombucha SCOBY underneath the surface of the tea. Yeast tendrils may form in the liquid, but you won't see new SCOBY forming in the liquid.
Tendrils, Dark Spots, Bubbles, Oh My!
These are all things that cause trepidation on the part of new brewers, but once you get used to the strange things you'll see, that initial skepticism will turn to awe every time you brew!
Yeast strands, totally normal; think of them as SCOBY hair
SCOBY yeast can often look slimy and even green - this is fine!
And below, the classic and spine-tingling Brown Visitor. Be careful when peeking at your brew before bedtime.
The Brown Visitor is just a conglomeration of yeast, and your SCOBY will probably grow around it. Bubbles are usually involved around the glob, too.
Below, also, are some common brown visitors. The specks on the surface (left) are often yeast granules that are at times tough and grainy, but are totally normal. On the right are just bits of tea that didn't get strained out during steeping.
Specks in the SCOBY
And finally, the giant SCOBY. Simply the result of a long fermentation time, there's nothing to fear here. The kombucha below this one will likely be pretty sour, but both parts can be used as normal. The kombucha as vinegar or starter, and the culture as a mother, backup or foodstuff.
Thick SCOBY is the result of vigorous metabolism and usually a long ferment
Don't Freak Out!So, next time your brew is weirding you out, remember that SCOBY lead lives of their own and don't bow to our expectations of understanding. If any of the above troubles you, let it be laid to rest. Remember that the ultimate test of a successful brew is good fun and great taste. Happy brewing!
Check out this blog post if you think your kombucha SCOBY may be performing in less savory fashions, i.e. growing mold