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3 Things That Cause Mold on a Kombucha SCOBY

Health YEABUCHA SCOBY. Read our quick read article if you are wonder what to do if you've got mold on your SCOBY

Mold - let’s talk about it. Everyone is afraid of growing mold on their SCOBY. The truth is, when we first started home brewing kombucha we had that fear too! But here’s what we learned: It’s REALLY hard to grow mold. We’ve actually found it to be a super uncommon problem. What most people think is mold, is usually just yeast which is essential to the brewing process. The symbiotic nature of kombucha actually PROTECTS your SCOBY from mold by creating an environment too acidic for other microbes to survive in (which generally takes 3 days, so if you’re mold free after day 3, you’re in the clear)! But if you’re still worried about mold, here are 3 things to avoid:

Not enough starter liquid & a weak SCOBY - If you compromise on quality, you open your brew up to the potential of moldy invaders. (Don’t worry-when you order your kit from YEABUCHA, you’re guaranteed to get the highest quality SCOBY and strong starter liquid). Make sure you always save 2 cups of starter from your F1 brew and make sure to not separate the layers of a single SCOBY -  you need that thick barrier to keep the mold out.  

Cold brew - Continuously having your brew temperatures fall below 64 degrees will slow down the fermentation process. Remember, it’s the fermentation that produces the acidic environment which keep unwanted mold away.  Keep your brew strong and healthy by keeping the temp in mid 70s - if it sounds like perfect weather to you, you’re SCOBY will love it too!

Brewing with flavored tea- When you introduce oils and other flavor compound into the first fermentation phase of your brew, the environment within your brew is altered. Essential Oils or other chemical flavoring, aka “natural flavors” may make the tea taste delicious, but it can harm the SCOBY, (which will inhibit the natural protection of your brew). We source the highest quality, organic black tea, that we know grows beautiful SCOBYs and brews delicious booch. If you want to try using flavored teas be sure to use only organic blends without any additives.

If in the off chance you do end up running into mold in your brew, you’ve got to throw it away. It unfortunately cannot be washed off or removed, and once it’s there it will continue to grow back. Go ahead and compost that batch and start fresh from your SCOBY Hotel! Didn't have a SCOBY Hotel set up? We’ve got you covered with our Single SCOBY to restart your brewing!

Below is a photo gallery of moldy SCOBYs. 

photo gallery of moldy kombucha SCOBYs

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  • The YEABUCHA Sisters on

    Using a store bought kombucha to grow a SCOBY can often create this problem with mold appearing. If you suspect mold, it’s best to toss the brew entirely as the mold contaminates everything and can make you sick if consumed. We recommend starting with a fresh SCOBY and starter liquid from a safe and reliable source, like us!

  • Avdy on

    I’ve used a synergy multi green kombucha to start my brew I think I have mold on the scoby… Or could this just be from the greens and be ok to drink…? Thanks

  • The YEABUCHA Sisters on

    Hi Carter- The origin of mold is sometimes tricky to pin down. There can be a variety of things that cause mold on a SCOBY. What sort of tea are you brewing with? We recommend organic black tea, free from any flavoring or additives. Even ingredients labeled “natural flavors” or essential oils can corrupt the brew and cause mold. Double check the tea you are brewing with doesn’t contain any of these ingredients. Next, check the temperature of the brew. If you are adding your SCOBY to the sweet tea when it is still hot, you can damage the SCOBY causing mold. You want to shoot for a brew in the mid 70s. Another cause could be something airborne. Check to see if you have any fruit or bread that has gone moldy near your brew. Lastly, in your brewing method, make sure you are using two cups of strong starter liquid from your SCOBY Hotel. 
    If you find you continue to have this problem, you may want to consider starting over with a new SCOBY & Starter Liquid to be sure there isn’t contamination in your Hotels

  • Carter on

    I have two healthy hotels that produce health scooby. When I transfer starter tea and healthy scooby for a new batch of Kombucha-mold appears on the fresh batch despite traditional sanitation methods. This has happened three times. What is going wrong?

  • The YEABUCHA Sisters on

    Hi Mayar! To brew kombucha you need to have a SCOBY and some starter (previously fermented kombucha). No one is really sure where the first batch of kombucha came from, but there are definitely some interesting myths out there. We actually have a whole blog post dedicated to it, which you can check out on the SCOBY section of our blog! If you are interested in getting started, you should check out our shop! We’ve got high quality SCOBYs and brew kits that provide you with everything you need to successfully brew kombucha! We don’t recommend growing your own SCOBY as that can lead to a weak and unstable brew, opening you up to mold! Please let us know if you have any additional questions! We’d love to chat and help you get started on your kombucha brewing journey!

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