Been looking at gravity in my doppelbock, started at 1074, calculated FG 1019, has been 'stuck' at 1028 for last 36 hours - raised temps from 12 to 15C for diacetyl rest but no longer any real airlock activity...
So - is it slow, or stuck, and is it worth rousing yeast at all or just waiting...
Had to repitch it after first yeast failed completely and re-hydrated it while dropping into new FV and pitched 2 packs of rehydrated brewferm which did really well for a good while but now seem to have slowed to nowt... I know lagers take longer but wondered if it's best to stir early or just relax and leave it to do its thing - will be away for 4 days over weekend so need to act tomorrow if its worth doing owt...
Cheers all steve
Looks like a sticking fermentation in doppelbock
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lancsSteve
Re: Looks like a sticking fermentation in doppelbock
brewferm lager that islancsSteve wrote: 2 packs of rehydrated brewferm
do have some tronzymol yeast nutrient as well.
Aeration was ok after dropping and re-pitch but possibly not as much as it could have been with shaking etc
just taken a peek as no airlock activity and level both sides. Kreasen head gone so think that might be that... Top temp was 15.4c for rest will be a bit sweet but not undrinkable though can it be bottled or kreasened?
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lancsSteve
Re: Looks like a sticking fermentation in doppelbock
In absence of ideas / suggestions I stirred it slowly today and added about 1tsp of tronxymnol yeast nutrient - will see if there's any effect for tomorrow
Keeping it at 15C
Keeping it at 15C
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dave-o
Re: Looks like a sticking fermentation in doppelbock
(at the risk of sounding stupid in case my suggestion is completely against this style of beer)
15c is still quite low. Maybe bumping it up to 18 or 20 would get the yeasties partying?
15c is still quite low. Maybe bumping it up to 18 or 20 would get the yeasties partying?
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crookedeyeboy
Re: Looks like a sticking fermentation in doppelbock
I was going to say the same thing but wasnt sure about the type of yeast as Ive never used it.
I would be inclined to say 12C is far too low for any yeast to do any kind of vigorous exercise...
I would be inclined to say 12C is far too low for any yeast to do any kind of vigorous exercise...
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steve_flack
Re: Looks like a sticking fermentation in doppelbock
Actually that's a perfectly normal temperature to ferment lagers at (with a proper lager yeast). In fact I ferment lower than that. You do need to pitch a lot of yeast though if you do ferment that cool - 1 sachet is going to be pretty slow.crookedeyeboy wrote: I would be inclined to say 12C is far too low for any yeast to do any kind of vigorous exercise...
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lancsSteve
Re: Looks like a sticking fermentation in doppelbock
pitched 2 packs but considering gravity and initial prob with first yeast and then dropping and re-pitching recon 3 would have been a better betsteve_flack wrote:You do need to pitch a lot of yeast though if you do ferment that cool - 1 sachet is going to be pretty slow.
no further activity or gravity drop this eve which is probably impatience getting the better of me
the good news is it tastes ok, sweet but nit sickly it's dropped 70% of the way towards calculated final gravity
so what now...
Wait longer and see if rousing and nutrients will help?
Raise temps more?
Or just acknowledge it's stuck but be thankful bock is a malty full bodied beer and just go to pressure barrel before bottling?
Steve
ps. Hi steve this was brewed in yor old mash tun/boiler you flogged to my bro-in-law karl aka mr c in Norwich a few years ago
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lancsSteve
Re: Looks like a sticking fermentation in doppelbock
guide temps are 10-15c for this yeast btw, too high and you'll get unwanted esters so typical is pitch at 10 ferment at 10-12 then raise toward end to 15 to reabsorb diacetylcrookedeyeboy wrote:I would be inclined to say 12C is far too low for any yeast to do any kind of vigorous exercise...
lager is a little more challenging than ale but with a cellar it's great and it's a good challenge!
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coatesg
Re: Looks like a sticking fermentation in doppelbock
With a starting gravity in the seventies, I would probably have pitched a fair bit more yeast (the calculator on mrmalty.com gives 35g of dry yeast as a figure - I'd happily pitch 4 here I think), which would explain why it's maybe a bit slow. Though, it may well be working away, you won't necessarily see activity.
Perhaps try rousing a little and leave it to work - how long has it been in the fermenter?
Perhaps try rousing a little and leave it to work - how long has it been in the fermenter?
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lancsSteve
Re: Looks like a sticking fermentation in doppelbock
Tried rousing earlier today
It's been in fermenter 10 days now was working well after a week then slowed /stopped after temp was raised from 12 to 15
My apparent attenuation is currently 62%, calculated fg of 1.019 was assuming 72% though as my figures for yeast are guestimates for strain (I can only find adjectival attenuation data of 'medium' not statistical). My current gravity once temp corrected from 15c to 20c calibration temp is 1.027 and expected fg could be as high as 1.022 if I was actually only going to get 70% apparent attenuation from this yeast
in short 1.028 dont necessarily seem so bad at all
would use 3 packs if doing this again, only bought two as they were 'emergency backup' if wyeast failed which it did.
As long as I remember probs and suggested soulutions this is a good one for experience and thankfully not an undrinkable brew - was never gonna be an easy one! Know more on getting wyeast prepared now and on dry pitching rates.
If
experience = (The sum of your mistakes) - the stuff you forgot
And I don't forget it all then this is all good learning
Away fir weekend so leave in fermenter after rousing or rack off?
Instinct says wait and see no rush.
It's been in fermenter 10 days now was working well after a week then slowed /stopped after temp was raised from 12 to 15
My apparent attenuation is currently 62%, calculated fg of 1.019 was assuming 72% though as my figures for yeast are guestimates for strain (I can only find adjectival attenuation data of 'medium' not statistical). My current gravity once temp corrected from 15c to 20c calibration temp is 1.027 and expected fg could be as high as 1.022 if I was actually only going to get 70% apparent attenuation from this yeast
in short 1.028 dont necessarily seem so bad at all
would use 3 packs if doing this again, only bought two as they were 'emergency backup' if wyeast failed which it did.
As long as I remember probs and suggested soulutions this is a good one for experience and thankfully not an undrinkable brew - was never gonna be an easy one! Know more on getting wyeast prepared now and on dry pitching rates.
If
experience = (The sum of your mistakes) - the stuff you forgot
And I don't forget it all then this is all good learning
Away fir weekend so leave in fermenter after rousing or rack off?
Instinct says wait and see no rush.
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coatesg
Re: Looks like a sticking fermentation in doppelbock
I'd leave in the FV - 10 days sounds like a reasonably short time for a ferment at lager temps (My bitters often sit in the FV for longer!)- personally, I'd leave it at least another week or even longer before even thinking about starting the lagering. Others with more experience in low temp ferments may have ideas on how long they would ferment a beer like this for 
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lancsSteve
THinking about carbonation and/or restarting fermentation
Another week and no change - SG stuck at 1.027
Been wondering what I could do, thinking about carbonation as well and reading info on that here: http://braukaiser.com/wiki/index.php?ti ... ng_Extract
The tast is pretty much fine - a little sweeter than I'd like but not a disaster at all. Want it to be pretty well carbonated (2.5g/l CO2 is 'typical' for style)
Have got some more of the same yeast now so was wondering whether its practical / desirable / stupid to try taking off about a litre or 2 of the beer as it still has ample potential fermentable sugars in to be fermented out (i.e. use this partially fermented wort rather than a more typical german approach of reserving unfermented speisse), re-aerating it and pitching the yeast into this (i.e. as a starter) to kreausen it and then putting that active starter back into the beer...
I'm assuming 2 things:
1 - potential fermentable extract makes this viable as an option which wouldn't be the case without a stuck fermentation.
2 - there's nothing intrinsically wrong with this approach with regards off flavours - at best it will restart a broader femrentation and at worst leave in some extra yeast to settle out
I hope this would work to at least carboante for bottling and ideally finish the fermentation - but is there any reason I've not anticipated to definitely NOT do this?
Cheers
Steve
Been wondering what I could do, thinking about carbonation as well and reading info on that here: http://braukaiser.com/wiki/index.php?ti ... ng_Extract
The tast is pretty much fine - a little sweeter than I'd like but not a disaster at all. Want it to be pretty well carbonated (2.5g/l CO2 is 'typical' for style)
Have got some more of the same yeast now so was wondering whether its practical / desirable / stupid to try taking off about a litre or 2 of the beer as it still has ample potential fermentable sugars in to be fermented out (i.e. use this partially fermented wort rather than a more typical german approach of reserving unfermented speisse), re-aerating it and pitching the yeast into this (i.e. as a starter) to kreausen it and then putting that active starter back into the beer...
I'm assuming 2 things:
1 - potential fermentable extract makes this viable as an option which wouldn't be the case without a stuck fermentation.
2 - there's nothing intrinsically wrong with this approach with regards off flavours - at best it will restart a broader femrentation and at worst leave in some extra yeast to settle out
I hope this would work to at least carboante for bottling and ideally finish the fermentation - but is there any reason I've not anticipated to definitely NOT do this?
Cheers
Steve
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SiHoltye
Re: Looks like a sticking fermentation in doppelbock
I know it's academic now but I've had it suggested to me recently that when dealing with dried yeasts in a cold ferment like you are maybe 6 packs might be up to it, poss 8 would not produce off flavours in 23l at 12degs C. Anyone tried that?
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lancsSteve
Gyle-worting/kreausening as a 're-starter'?
WOuld def use at least 3 next tim - that said next time I'd not use dried yeast at all but make sure my liquid yeast was viable and pitch a HUGE starter... Bad set of circumstances.
Hope SHop were VERY helpful and advised me that info on wyeast site (which I'd followed) wasn't best - with an old smack pack you need to allow one DAY per MONTH since date of manufacture and not to use it until totally swollen - and then pitch it into 2l starter and keep in warm area. I did none of that (waited 24 hours, pitched unswollen and then kept at cool temps of 13c).
However the question remains:
- would drawing off some of the wort at 1.027 with expected FG of 1.019, aerating and using as a 're-starter' work to help carbonate the beer?
or
- should I try gyle-worting/kreausening with a fresh starter made from DME?
AM still somewhat hopeful that by re-pitching for carbonation I might see a last gravity drop if I'm lucky e.g. if balance of aearated re-starter is enough to get fermentation going in that and then pitched into the wort...
*could* try a mix of say .5l DME starter with 1.5l wort...
If I hear nowt shall experiment away and maybe bottle a couple before trying this to compare/avoid total loss.
Hope SHop were VERY helpful and advised me that info on wyeast site (which I'd followed) wasn't best - with an old smack pack you need to allow one DAY per MONTH since date of manufacture and not to use it until totally swollen - and then pitch it into 2l starter and keep in warm area. I did none of that (waited 24 hours, pitched unswollen and then kept at cool temps of 13c).
However the question remains:
- would drawing off some of the wort at 1.027 with expected FG of 1.019, aerating and using as a 're-starter' work to help carbonate the beer?
or
- should I try gyle-worting/kreausening with a fresh starter made from DME?
AM still somewhat hopeful that by re-pitching for carbonation I might see a last gravity drop if I'm lucky e.g. if balance of aearated re-starter is enough to get fermentation going in that and then pitched into the wort...
*could* try a mix of say .5l DME starter with 1.5l wort...
If I hear nowt shall experiment away and maybe bottle a couple before trying this to compare/avoid total loss.