View Full Version : Mold problem

Los Hidromieleros
09-08-2008, 05:56 PM

I think that we have a problem with mold.

We have two 5 litre glass bottles in which we are trying to make mead, but it seems as if there is mold growing on the surface of the must. The must has no added brewer's yeast (two other bottles with added yeast do not have this problem and are almost done). We started the fermentation almost two months ago.

In one bottle (in which we used about 1.2 kilograms of honey in 5 litre total volume) there is a thick layer of foam on top, most of it is white but it has some black (or maybe greenish) parts. It smells of mead. Here is a photo:


The other bottle (in which we used about 0.8 kilograms of honey in 5 litres) the layer is not so thick and is white with a powdery apearance. There is no smell of alcohol, but a bit of smell of honey. Here is the photo:


Note: the bottles are of green glass so everithing looks greener.

Note 2: We added nothing but the honey and the water. We boiled he water honey mixture. We did not use a valve, we just covered the opening with a piece of fabric.

So, do we have a mold problem? If so, what can we do about it?


09-08-2008, 06:20 PM
It appears that you do have a mold problem. There is only one procedure to follow at this point and this will only work if the mead under that fungus cap still tastes and smells OK. First, rack out the liquid from under the cap into a clean carboy while taking care to disturb that cap as little as possible. Then treat the mead in the clean carboy with potassium metabisulfite to bring the level of free SO2 up to 100 ppm. That free SO2 value will depend on the pH of the mead, so take a pH measurement of the must once you've got it out from the mold, if you can. Then stopper the carboy with an airlock and hope that you've got enough sulfite in there to kill off any mold spores that came along as you racked the mead. If, after several weeks, you have no evidence of further mold growth, then you are OK. If the mead finished too sweet you can try at that time to pitch a strain of commercial wine yeast, perhaps after taking time to acclimate it to your must.

This might work, but I have to tell you that your odds of success are only about 50% at this point, especially with the batch that has the bigger mold cap.

I'd recommend that you read the newbee's guide to meadmaking, available from the main GotMead page, and pay special attention to cleanliness and sanitizing technique. Then you can try again -- and I also recommend using a commercial strain of yeast next time, rather than trusting that whatever lands on the must from your environment will ferment it properly.

Good Luck!

BTW - Welcome to "GotMead?"!!!