View Full Version : Stuck fermentation, not sure how to proceed

02-19-2015, 05:26 PM
I'm working on a 2 gallon batch of traditional mead (in 5 gal bucket). Fermentation has been slow all along, and now seems to have pittered out almost completely.
I used Lalvin D47 with the intention of letting it reach it's alcohol tolerance (14%) so that I finish with a sweet mead without using sorbate/campden.
I used GoFerm (5 tsp when hydrating) and Fermaid-K (as described below).

I don't have weights on honey, but kept pretty good logs of my gravity readings.
1/3/2014 1.115 about 2 gallons total volume currently....roughly 1.5 of that was spring water. must was room temperature around 68F. stirred with MixStir on my drill
1/4/2015 1.112 at about 17-18 hours from pitch, added .75 tsp of Fermaid K. also drizzled in about a cup of honey while stirring with drill stir. Gravity now at 1.115
1/5/2015 1.112 poured in additional honey. aerated with drill stir. Gravity now at 1.122
1/6/2015 1.118 aerated with drill
1/7/2015 1.115 gently degassed by hand with spoon
1/8/2015 1.114 65 degrees. Spoon used to degas
1/10/2015 1.106 65 degrees. Degassed with spoon
1/12/2015 1.096 Added a little more than 1/2 tsp fermaid k (mixed in hydrometer tube, ran through funnel filter)
1/17/2015 1.084 66 degrees. Degassed with spoon
1/22/2015 1.073 65 degrees. Degassed with spoon
2/5/2015 1.062 degassed with drill. 63 degrees. Moved to warmer room
2/9/2015 1.058 Degassed with spoon. 73 degrees. Moved to basement. Placed on heat pad on low. Taste was harsh compared to all previous readings.
2/10/2015 No Gravity reading. placed on aquarium thermometer. 64 blue, 68 brown. Raised heat to medium
2/11/2015 68 degrees blue-green.
2/14/2015 1.054 68 degrees green. degassed with drill. 71 degrees internal. Taste settled back down.
2/15/2015 1.053 68 degrees green. degassed with drill. 71 degrees internal. PH strip was between 3.6 & 4. Per LHBS, added more Fermaid K (1/2 tsp)
2/19/2015 1.052 68 degrees green. degassed with drill. 71 degrees internal. Racked for fear of lees, to a 3 gal carboy. To help ensure accuracy of gravity readings, I used vinometer and it came out around 9%, which is right in the ballpark.

Any suggestions on how to get these yeasties going? I'm looking for a sweet, so don't really want to pitch 1118.
Or, am I just being too impatient?

02-19-2015, 06:17 PM
Out of curiosity why the 5 gal bucket?

02-19-2015, 06:59 PM
This is only my second attempt at mead.
First batch I had quite a few blow ups while aerating in a carboy.
5 was the smallest bucket lhbs had.

Medsen Fey
02-19-2015, 10:22 PM
The 5-gal bucket is just fine - no MEAs that way.

I'm wondering if your gravity readings may have been off. If you didn't fully de-gas the samples, it might cause your readings to be a bit higher than actual, and then when honey is mixed in you get an accurate reading. When you add a cup of honey, the expected increase in gravity should be close to 14 points in a 2-gal batch. Then you added more honey giving another 10 point (or possibly more) increase. That would translate closer to a starting gravity of 1.140 and if that is the case, your actual ABV currently may be closer to 12-12.5%. A vinometer is WORTHLESS when you have a sweet batch - they're not very reliable even with a dry batch.

You can try adding some yeast hulls 1 g/gal and a couple of grams of Epsom salts. When you racked it you left behind most of the active yeast in those lees. You can give it more time and see if it gets a bit farther, and the yeast may rebuild some mass. However, if you don't want it this sweet, you're probably going to have to pitch another yeast, or make a dry batch and blend it in. For future batches, avoid the honey additions and let it ferment to completion before racking.

Endeavor to persevere!

02-20-2015, 09:01 AM
Thanks for the reply.
Definitely learned my lesson about when to feed the honey.
Good thoughts on the gravity readings. I'll weigh my honey when I get home. I started with a 12lb bucket from silverbow. Although I'll have to guess a bit on the weight of the bucket and how much my wife stole for her tea.

I was surprised at how little lees was there. I've wondered if my aeration was too aggressive. The batch turned quite cloudy very early on. Makes me wonder if alot of yeast is suspended (although inactive).

I hadn't read anything about yeast hulls and epsom salt for stuck fermentation, but it looks like Fermaid K already includes them.
Is it still worth adding? Any negatives of adding them?

I'll start looking for the hulls. My lhbs (thebrewmentor.com) doesn't appear to have them.
They do have a Nutrient with dap, hulls, mag sulphate, Vitamin B.
But, I imagine you listed hulls and epsom explicitly because I'd want to avoid adding DAP at this point. Is that right?

Medsen Fey
02-20-2015, 09:19 AM
DAP is useless at this point. The yeast really can't assimilate it.

Your aeration wasn't too much (During active fermentation you aren't going to do any damage with aeration)

The cloudiness is due to suspended yeast. It can take many weeks to clear even after fermentation is done.

If you don't have yeast hulls handy, boiling some bread yeast may be able to accomplish the same thing.


02-20-2015, 09:36 AM
And if I do pitch yeast again, would I be ok to go with D47 again?
Or is there a different yeast you'd recommend (hopefully something with a lower tolerance than 1118)

Medsen Fey
02-20-2015, 09:44 PM
D47 isn't going to help or it wouldn't be sticking. There are only a few yeast that are good for restarting a batch. Uvaferm 43 is king. EC-1118, DV10, QA23 are also good but all of them have high ABV tolerance. There is no getting away from that with restart yeast.

02-26-2015, 07:16 PM
Kind of covered all the bases already, Medsen did.

Just wanted to add that K1V-1116 is the king of fermentation restarting yeasts. It's another high ABV one though.

Medsen Fey
02-26-2015, 11:50 PM
Sorry Deezil, but K1V is not the best restart yeast which is why I didn't mention it. There's a thread in the patron's area (IIRC) which has a link to a nice scholarly study that showed other yeast including QA23 and EC-1118 as better. The encapsulated uvaferm 43 (pro restart) is the undisputed restart champion.

02-27-2015, 12:53 AM
That's news to me, it's touted all through Scotts Lab's publications as the go-to for restarting fermentation.. Guess I'll dig a little deeper, thanks.

You're right about Uvaferm 43 though, but for some reason my thinker always skips over the encapsulated yeasts.

Medsen Fey
02-27-2015, 07:51 AM
Here is the thread I was mentioning - http://www.gotmead.com/forum/showthread.php/20735-Restarting-with-non-acclimated-yeast
And I was in error. It is not EC-1118 that was tested in this article but L2226. It was another article elsewhere that was looking at EC-1118. K1V is listed by Lallemand as being good for restarts (3 on a scale of 4) along with EC-1118 and DV10 and others, however, having had more than my fair share of difficult fermentations that I had to unstick, I can tell you from experience that K1V just doesn't work as well as these others. Don't get me wrong - I love K1V and it remains my favorite yeast, but this is one job where I think other alternatives really are better.

02-27-2015, 08:28 AM
Thanks for the suggestions on yeast, though I think I'll just give it a try with the hulls (got them in the mail) and epsom and time, and see if the yeast starts up on it's own.
I do like mine pretty sweet. I was targeting 1.03 (and was a bit worried it'd be too dry).
If they don't rebuild, I'll probably try oak & acid and see if I can mellow that sweetness.

Medsen Fey
02-27-2015, 09:25 AM
You can also make a dry batch and blend.