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View Full Version : Stuck Mead - but I have options.. opinions welcomed



schlapppy
04-12-2011, 10:06 PM
My Apricot mead seems to have either drastically slowed, or downright stopped.

Link to Apricot Mead brew log (http://www.gotmead.com/forum/showthread.php?t=17602)

I ran out of DAP tonight (what timing.. i'll buy more tonight online)

Heres what I think my options are..

Use lees from other active brew
Make a strong starter w/ same yeast
Wait til more DAP comes in.. be patient.. see if brew heals itself


As far as what lees I can steal.. I have 2 active fermentations.

My version of Wayne B's Christmas Spice Metheglyn (http://www.gotmead.com/forum/showthread.php?t=17849) is practically done. I probably should rerack into a carboy anyway. This could be put some wasted lees to good use. This does use D47 instead of 71B

or.. Slappy's sweet cherry melomel (http://www.gotmead.com/forum/showthread.php?t=17850) This is using 71B.. and actually the same honey. I'm leaning towards this option so the yeastie beasties don't need to duke it out.

Thoughts?

schlapppy
04-12-2011, 11:53 PM
on second thought... I do have activity in the air lock. About 1 bubble every 10-20 seconds. This may be able to be nursed back to health with just ferment-K, daily aeration, and this increase in temperature. The DAP will help too, but I don't have any right now. If I was able to add some of the lease from the cherry mel, i'm thinking it'd take off like wildfire... but maybe that's not necessary.

wayneb
04-13-2011, 06:53 AM
You may simply be at the point where your yeast can't handle any more ethanol in the mix. This was a rather high initial gravity must if I remember correctly, and 71B doesn't usually like to perform much above its nominal ethanol tolerance unless you are very attentive to the ferment early on. It can be pushed past nominal, but that usually takes a careful regimen of staggered nutrient doses along with periodic stirring throughout primary.

Actually, this late in fermentation DAP probably won't help. As the yeast are subjected to a more and more alcoholic environment, their cell wall membranes change, eventually making them unable to take up nitrogen from inorganic sources like DAP. So for reviving a stuck or very sluggish fermentation, yeast hulls (or yeast ghosts) are often recommended. They do two things - first, they are a source of organic, amino nitrogen, which the yeast can still use even rather late into the fermentation. Second, and more importantly, the autolyzed bits of yeast cell wall in the hulls attract and bind with many common yeast toxins, and then they fall out of suspension and are trapped safely in the lees layer where they can't stress the living cells still fermenting in the must. So for a really sluggish ferment, I always try yeast hulls (after things like a temp change and slowly stirring the must, like you've already done) before doing anything more drastic. Attempting a full-blown restart is challenging at best - and sometimes despite everything you do, it won't work.

Medsen Fey
04-13-2011, 07:02 AM
Have you checked the pH? Since you are making a traditional mead here and haven't added any fruit, you may be seeing the effect of a pH that is too low.

schlapppy
04-13-2011, 09:06 AM
What kind of stirring should I do as far as stirring (drill & long spoon)?

O.G. 1.132
S.G. 1.073
So that's only ABV of 6.667%. I'm guessing it's not done.

I don't have a pH meter.. but this mead is making me wish I did. I think I bought some of those strips a while ago... i'll see if I can find them and take a reading tonight.

I ordered some yeast hulls and DAP. I guess I'll lay off the DAP in this thing, and wait for the yeast hulls to come in the mail.


Medsen & Wayne, Thanks for your responses and suggestions.

wayneb
04-13-2011, 10:46 AM
I'm not sure how you're calculating your ABV - 1.132 to 1.073 is closer to 8.3% by my calculation, but nevertheless you are right - 71B shouldn't be giving up the ghost just yet. I forgot that you hadn't added the apricot puree yet. Medsen is right to suggest that this might be a low pH thing. Even if you can't test the pH, you can safely add about a TBSP of potassium carbonate or potassium bicarb (that's roughly 3/4 gram per gallon - dissolve it in a little water first to prevent MEA - adding it dry will release LOTS of CO2). Do that, and then see if fermentation picks back up. If not, then add the hulls when they show up.

From hereon out your stirring should be as slow as possible; trying only to mix the surface layer of lees back up into the main must. Consider it to be more of a rousing of the yeast rather than any kind of hard mixing from this point forward. Prior to now it would have been OK to introduce oxygen through vigorous stirring - but now your yeast really can't use much more.

It could also be that you provided enough in the way of benign neglect, that this fermentation will just proceed along very slowly. Sometimes that happens, especially if the yeast are nutrient starved (although that often gets them to put out H2S), or are oxygen starved early on in the fermentation.

Medsen Fey
04-13-2011, 12:56 PM
One other alternative would be to go ahead and add the fruit puree now. If there is a pH problem that will likely correct it. If there is any nutrient deficiency that will probably take care of it. That may be your simplest way to get things moving.

schlapppy
04-13-2011, 04:58 PM
One other alternative would be to go ahead and add the fruit puree now. If there is a pH problem that will likely correct it. If there is any nutrient deficiency that will probably take care of it. That may be your simplest way to get things moving.

Good idea. I'll give this a go tonight.

schlapppy
04-13-2011, 10:43 PM
Good idea. I'll give this a go tonight.

Done. I'll keep the results posted the the brew log. Thanks for your help everyone.