First up, don't be alarmed, the floaties you've found are completely safe to consume.
A black scoby is a sign of a kombucha culture that has been contaminated or is worn out. It takes a long time and many batches before a scoby is worn out.
Your SCOBY and, more importantly, your kombucha brew will be just fine. The position of the SCOBY pellicle, during your kombucha brew, is irrelevant. The placement of the SCOBY should never be used as an indicator of the health of your kombucha batch. Your SCOBY may sink, float, or hover in the middle, pay no mind.
A moldy or dead scoby is quite distinctive, and there is no mistaking it when you see it. The mold will be white or colorful, fuzzy and dry. It can appear as spots on the scoby, or cover the scoby altogether. A dead scoby will be black.
Your main concern with an active brew would be mold. Unlike yeast, mold is fuzzy in appearance. When it forms on kombucha, it will usually be either blue/green or white. Regardless of color, it will always look fuzzy and dry whereas you SCOBY and yeast will look wet and slimy.
Kombucha Mold Identification
Those blue circles of mold are the problem, while the white circles of SCOBY growth are normal. Powdery tan mold covers much of a new SCOBY – mold is always DRY! White fuzzy dry mold is easy to spot.
Kombucha Mold Identification
Mold will usually appear as fuzzy, green, or black growth on the surface of the SCOBY.
Do not ingest any of it or try to “save” it. A moldy brew is a lost cause, unfortunately. You cannot salvage a SCOBY that's already been infected with mold. Clean and sanitize/sterilize all equipment that's come in contact with your kombucha and start over with a new SCOBY and new starter tea.
The build-up you see at the bottom of your kombucha is simply an array of yeast and bacteria cells that have settled to the bottom of your bottle or brewing vessel.
During your brew you will notice that a new scoby will start to form as a thin white layer on the top of your brew (or as a new layer on the top of your scoby if your scoby is floating on the surface of your brew). This scoby should be gently removed when your drink is ready and stored with the mother scoby.
This secondary fermentation also creates that little floating bit of SCOBY. But, if you see greenish or pinkish “stuff” floating, it can be a sign of mold and that your kombucha has gone bad. It's best to just toss it and buy a new bottle.
Sediment: When you shake a bottle of kombucha, you distribute the particles throughout the batch, changing the true taste of the brew. Although harmless, some people do not enjoy the texture of the sediment, and when shaken, it will disperse throughout the beverage.
Mold, which is usually fizzy and colored, is a sign that your kombucha has gone bad.
As a result, the SCOBY can produce harmful bacteria and aspergillus (a toxin-producing fungus), which can cause illness. I loved brewing kombucha, but I didn't want to make myself ill from it. I decided to stop brewing.
Discard SCOBYs that rip or tear easily. Thick cultures can still be weak. To test it, pinch the SCOBY between the thumb and forefinger; if it easily presses through, the culture can be let go. Sometimes weak culture can be attached to strong culture.
But if you do experience mold, it will develop on the top of your brew, where it's exposed to oxygen. If you do experience mold, you MUST DISCARD EVERYTHING and start with a new SCOBY and starter liquid from your SCOBY HOTEL, or purchase a new SCOBY from us!
The most common moulds found in kombucha tea are Aspergillus and Penicillium. Not only can these moulds produce toxins as they grow, they also use up the acid and raise the pH to levels where any food poisoning bacteria present can grow.
COntaminated kombucha can be dangerous
If your kombucha becomes contaminated with fungus, mold, or bad strains of bacteria, it can be dangerous to consume (regardless of how healthy your immune system is). Contaminated kombucha can cause stomach upset, allergic reactions, nausea, head and neck pain, and even death.
The small brown or black stringy clumps are colonies of yeast and tea residue. They are completely normal and safe! These colonies often form long filaments that hang under the kombucha scoby.
For now, you should know that your mother SCOBY can sink, float at the top, float sideways in the middle—it doesn't matter what position they are in. In fact, they will likely move throughout the brew!
The easiest way to store your kombucha scoby is in a sealed container in the fridge. Always label the jar so that no one in the household gets rid of it by mistake! The scoby then goes dormant and can be stored for up to 6 months.
You don't really have to worry about killing your SCOBY unless the liquid reaches above 100 degrees F. If this happens, you could: Move your vessel to the coolest, darkest spot in your home. It's OK to keep it in a closet and just take it out at night when it's less hot.
But if that doesn't happen, that's just fine as well. At around day 3, you'll start seeing some opaque white specks dot the top. This is usually when people get nervous, thinking it's mold. It's really just the SCOBY starting to get into formation.
Overconsumption can lead to headache, nausea, gastrointestinal distress, or ketoacidosis. There are a few populations that should never ingest kombucha. Pregnant and breastfeeding women, children, and individuals with liver or kidney disease, HIV, impaired immune systems, and alcohol dependency should avoid kombucha.