Suddenly appeared - is it mold or yeast

[MeadMeInThePines]

Still new to mead making but I’ve never had anything like this happen. I made a gallon using half gallon of pomegranate juice and 2.25 lbs of honey back in March. I racked and added a pound of blueberries. A couple weeks later I re-racked and pulled the blueberries. Early June I cold crashed it, added 12 oz of blueberry simple syrup I made to backsweeten it and re-racked it again adding in pot sorb. It’s been sitting since clearing nicely. Last week I opened it to take a small sample (I did this on several others too, but this only happened to this one). The pom was still very tart (the pom up front and blueberry on the back is really tasty) so I added 1.5oz of honey. 2 days later this floating gook catches my eye. I’m pretty careful about sanitizing. I used the same honey and tools to backsweeten some other meads at the same time without issue. I didn’t have a bubbler on this carboy because fermentation had stopped a while ago, but when I opened it to give it a sniff, there was a pressure release. Could the honey have triggered fermentation again? I thought it was mold but it smells fine, there doesn’t appear to be any threads, fur, green color, etc. I added another 1/2 tsp of pot sorb and after burping the cap a couple times in the past week, there isn’t much gas escape now. It hasn’t grown in size or changed noticeably at all, nor has it fallen to the bottom.

If there’s any chance its mold, I’m just going to dump it. But I figure at this point its a bit of a science experiment. Like I said, the sample prior to this happening tasted pretty amazing so if its just a new yeast raft, then will it eventually drop? It’s hard to get a good pic through the glass and the one through the neck doesn’t show much surface, but its the best I can do.

 

[darigoni]

How come you're not using potassium metabisulfite?

 

[LaPixie]

From the sound of it, it could very likely be refermentation due to the backsweetening. Cold crashing only stops fermentation temporarily, so I always use both k meta and k sorbate to fully halt fermentation, at least a full 24-48 hrs prior to any backsweetening or secondary flavor additions that add fermentable sugars (such as berries). You can either put a bung and airlock back on and let it run in its course, then stabilize and backsweeten again, OR try adding the k meta (and more sorbate) to stabilize now and hope for the best, though I typically wouldn't recommend it during active fermentation. Don't dump it yet, wait and see if it truly is refermentation. (The pictures also don't look like mold to me, and you can clearly see bubbles in it as well, so one more reason to wait and see!) Best of luck!!!

 

[Squatchy]

Pt sorbate only stops mead from reproducing. You want to use sulfites, too. They won't work until fermentation is over. Just dump it. It's only a gallon.

 

[MeadMeInThePines]

Since I don’t need the carboy right now, I decided to let it sit and see. No change in size/color/smell since my OP. I sucked some out today and its gelatinous. The mead underneath smelled and tasted fine (although it was much more “red wine” tasting than it had been prior, actually losing a lot of sweetness I was trying to add).

I was reminded by my better half that I had this same gelatin type substance when I took out the last fruit bag on another batch. I didn’t think much of it at the time because I’d assumed some of the fruit material had come out of the bag. I just strained it off the top and racked it. Along with that reminder was also the reminder this was the first time I’d used this particular raw unfiltered unpasteurized honey. It’s not the honey I used to make this batch, only to back sweeten.

At this point I am leaning towards refermentation as suggested above. I hadn’t been aware of using sulfites (part of the fun is learning) and in my prior batches, I’d used pt sorb as a “safety” (which was probably not the case given Squatchy’s comment) before bottling, being pretty confident the yeast had run its course.

I have another wide-mouth jar so I’ll probably just rack it, strain off what gets sucked over, and see what happens now that it sounds (and smells and tastes) like it’s not an infection.