View Full Version : Renewed Fermentation, AKA Bottle Bombs, AKA $!@#$!#$

12-22-2009, 07:46 PM

*Deep Breath* *Count to 10*

Right, so it looks like my problem with corking may in fact be due to renewed fermentation. I now see signs of air in every bottle, as well as clearly visible sediment. Here's the process I went through in preparation for bottling. Please tell me where I went wrong.

1: Bulk aging complete, one carboy at 6 gallons, one at 3 gallons
2: Stabilize w/ potassium sorbate. 3.5-4 tsp in large, 2 tsp in small (directions say 1/2 tsp per gallon). Stir.
3: Due to equipment problems, wine sits for another month or so.
4: Make up backsweetening mixture in same proportions as original must (apple juice, honey, spices).
5: Add 1/16 tsp sulfite to kill wild yeast (directions call for 1/4 tsp for 5 gallons). Stir.
6: Heat to below boiling, simmer on low heat for 15-20 minutes. Allow to cool to room temperature.
7: Add pectin enzyme and 1 tsp sorbate for 5.5 qts. Stir. Place in fridge overnight.
8: Mix backsweetener w/ mead, add additional 1 tsp sorbate, stir.
9: Allow to settle overnight.
10: Filter with #1 Buon Vino pads (mini-jet).
11: Rinse bottles with full strength sulfite solution, rinse again with 1/8 strength solution.
12: Fill bottles 24 bottles.
13: Cork 24 bottles.
14: Look at bottles 3 days later, curse a lot.

Now, the question becomes, how to procede from here. Do I put it all back into a bucket, add more sorbate, filter again, and re-bottle? Just add a small bit of sorbate to each bottle and re-cork? Give up and take up knitting?

Thoughts, comments greatly appreciated.

- Brett

12-22-2009, 08:29 PM
Do you have an extra refrigerator you can put these in? I know you have a lot of bottles, but that would give you some peace of mind while we figure out if there's an issue. Perhaps the garage is cold enough to 'cold crash' but not too cold to break the bottles?

Can you please provide a brewlog for these batches? That will allow the mentors to pinpoint your issue. Include yeast, gravity readings, time you bulk aged, etc.

12-22-2009, 08:51 PM
Hey Brett,

Well, I had a similar experience with my #2 batch, where after I had bottled a bulk-aged and very will cleared mead, it quickly threw out sediment/floating wisps of ??

As it turned out, the mead wasn't getting "bubbly", so re-fermentation probably hadn't started, but I couldn't give them as gifts. So I ended up pulling the corks, racking the mead back into gallon jugs onto sulfite first (again), and then two days later, I sorbated them. I now am letting them sit until I'm ready to re-bottle.

As to your efforts, the only thing I noticed is that you didn't sulfite prior to sorbating for your stabilizing steps. Since sorbating won't stop an active ferment, is it possible some yeasties lived through your small amount of sulfiting?

In any case, using the mini-jet filtering system, I've read that for bottling, you should run the wine/mead through the #3 filter, as that will remove most (not all), of the yeast; basically, a sterilizing filter. It may be prudent to step through the #2 filter first to ensure you don't "clog" the pump.

Not much help, but I'll bet filtering will "clear" (pun intended) this issue up for you.


12-22-2009, 09:08 PM
Brewlog - http://www.gotmead.com/forum/showthread.php?t=13905

12-22-2009, 09:17 PM
epetkus: Hrm..... Well.... that was stupid of me now wasn't it? It says right there in the Newbee guide doesn't it. This is what happens when you don't look up every step, every time, until you've done it 100 times.

Whee.... ;D

12-22-2009, 09:44 PM
Ha! Yeah, if we all read first, then made mead after, the world would be less mead filled and we would be "robbed" of such valuable learning lessons!!

Don't sweat it! As McFeely is fond of saying, step back, relax, drink some mead and then deal with the issue!


12-23-2009, 02:08 AM
So if I am reading your steps correctly, you added sorbate to the main batch but did not add sulfite? You did add sulfite to your backsweetening mixture, however. Correct?

This is probably your problem. Without sterile filtration or waiting a really, really long time, sorbates are not enough to stop more fermentation from happening. You need to use both sulfite and sorbate in the main batch.

12-23-2009, 02:01 PM
I'm not a patron at the moment (damn recession) so I can't read your brew logs, but akueck is good. He has a good and valid point with the sulfite and sorbate.

I'm going to assume you have gravity readings after backsweetening. (I know, never assume...) You should open one of the bottles and take a gravity reading. Assuming you have readings from before bottling, you'll have an idea if it's re-fermenting. You can also look to see if there's any pressure in the bottle or carbonation to the mead. If you don't have gravity readings after backsweetening, I'm not sure how to proceed. I wouldn't want to recommend waiting a few days and taking another set of readings, especially if it is re-fermenting. On the other hand, I know how much work bottling is so I don't want to recommend racking this back if it’s just a few slipped corks from overfilling/similar. Maybe a mentor will have better advice.

BTW, were you able to move these someplace cool to slow fermentation if the yeast are still alive and active?

12-29-2009, 10:25 AM
I did not take gravity readings after sweetening. I didn't consider the information to be worth anything, as I wasn't anticipating any renewed fermentation. For purposes here, I think it's a good bet there was renewed fermentation. The appearance of air, plus more yeast, is a pretty good bet they were getting down. When I opened one bottle, it had a bit of fizz to it.

I poured them out, added sulfite (1/4 tsp for 7.5 gallons), refiltered it (1 and 2), rebottled it. That was two days ago, and we seem to be fine. A bit of cork slippage, but so far no signs of air building up or additional yeast. Cross your fingers, knock on wood.

Medsen Fey
12-29-2009, 10:55 AM
I'm not quite sure why you are hurrying to re-bottle something that just had fermentation in the bottle.

Filtration is wonderful, but unless you are using an absolute membrane filter with a pore size of about 0.6 micron or smaller, you aren't removing all the yeast. The typical pads for most filters are nominal filters and even a 0.5 micron nominal filter will let yeast cells through.

Sorbate and sulfite together can stop the yeast, but not very well during active fermentation in most cases. They are better at preventing fermentation from restarting once the yeast have gone dormant. The dosing can also be an issue - honey can bind a lot of SO2 and if you aren't measuring the free SO2 (in conjunction with the pH), you can't be sure you have enough molecular SO2 to be effective.

This is my long-winded way of saying that if you have a batch that is experiencing refementation, the last thing you should do is rush to bottle it up again. It is better to dump it back in the carboy, and let it sit until it is certain that the gravity is stable at room temp for a few weeks. Then re-bottle.

Keep a close eye on those bottles, and if any get fizzy, empty them out and let the fermentation stop.


12-29-2009, 03:35 PM
Eh, the rush is this stuff was supposed to be done a month ago, so I could pack up all my equipment in preparation for a cross country move. Also, I intended them to be Christmas presents.

We'll see. I put the bulk of them out in the garage, keeping 6 bottles sitting on the counter at room temperature. We'll see if any of them blow up over the next week.

I suppose the worst that happens is a bottle bomb kills my boss..... Making room for me to get a promotion! ;D