Options for slowed/stuck fermentations

[TheGiantGinger]

Hey all,
I've been brewing two meads that have had some difficulty and would like some suggestions. Both are well within their ABV tolerance range, stalled at one point due to cold temperatures but have been brought up to a happier range, had all their nutrients added at the beginning and are now past the 1/3 sugar break.

Dry Mead 10L 6/5/13
3.5kgs Wildflower honey
3 tsp Lalvin D47
2 tsp Yeast Nutrient
4 tsp Citric Acid
1 cup strong black tea
1 tsp Malic acid

Started at S.G. = 1.109, last checked July 4th at 1.06. Stalled for a while when temperatures went below 14˚C, but now seems to be dropping .01 point a month.... the time isn't a huge issue... but in a couple of months temperatures will likely go way above D47's happy range.

Raspberry Mead 5L 17/3/13
2.2 kg honey
700g Raspberries
Juice from 1 lemon
Juice from 1 lime
3 tbsp strong tea
25 raisins
1 tsp Lalvin EC1118

Original SG = 1.101. It was racked to get rid of the raspberries a week later (and therefore also the raisins) and 1 L of water added. It got real cold at one point and stopped, but is now being kept at about 23˚C. It started up again but after only dropping .01 point in just short of 2 months... It looks like it has stopped now at 1.015. So this is more problematic of the meads.

From my understanding... adding any more nutrients at this point won't do anything for them. Both are well within their alcohol tolerance range (only at 6.77% of 14% and 12% of a possible 18% respectively) but seem to need some encouragement. Is there anything I can usefully do right now?

Thanks

 

[fatbloke]

Well at a glance, I'd say that you'd need to be checking the pH.

Both have acid additions up front, which is now a discredited method. The honey alone is more than acidic enough for the yeast......

If the pH is about 3.0 it's likely to slow the ferment, if it's dropped below 3.0, then it's likely to stall......

And potassium carbonate is the answer with either of the above.....

 

[Chevette Girl]

I second Fatbloke's suggestion, pH strips are pretty inexpensive and so is the potassium or calcium carbonate to correct it... and if you check the pH and that's not it, you can always add microwaved bread yeast, the living ones will cannibalize whatever they need from the dead ones and the remaining stuff will just settle out in the lees.

 

[loveofrose]

After you correct your pH issue, it still may not start up. I had this happen before. If it does not, get Uvaferm 43. If a starter of Uvaferm 43 doesn't kick it off, nothing will!

 

[Medsen Fey]

The pH could certainly be a factor. You could also try adding a dose of yeast hulls (or some Fermaid O, or even some GoFerm) and a bit if aeration.

Sent from my DROID RAZR using Tapatalk 2

 

[TheGiantGinger]

An update:
Adjusting the ph certainly helped the Traditional mead speed up it's fermentation as it's dropped .04 in the last month... however the Raspberry doesn't seem to be affected. I've also now added some more nutrient, but it doesn't seem to be starting up again. Is this where I would add some more EC1118 and treat it as a stuck fermentation? Or should I just wait until the Traditional finishes and use some of that to mix it down to an acceptable sweetness?

 

[Naveed123]

posting

adding a dose of yeast hulls

 

[loveofrose]

After re-reading you post, I calculated the raspberry mead at 15.5% ABV. I seriously doubt you will restart that. FG of 1.015 is not bad and may actually be better for a melomel than dry.

How does it taste?

Sometimes we get so technical and so ingrained in our expectations that we forget the only thing that matters... Does it taste good?

BUT, if you want to bottle, you will definitely need to stabilize it to avoid glass grenades.

 

[Medsen Fey]

BUT, if you want to bottle, you will definitely need to stabilize it to avoid glass grenades.

Yep, the only sure way to get a batch like this going again is to bottle it.