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Can Yeast Attenuate So Much The Beer Won't Carb?

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Mr. No-Tip

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So I had the highest hopes for my first Double IPA, but it's turned out to be a pretty rough trot.

It was a good lesson in the concept of yeast attenuation, and actually pushed US05 beyond it's range to 77.7%. So I accepted my 1018 FG only to underestimate my carbonation. The forum then provided some advice on how I might recarb the bottles.

Tonight I compared two bottles that I'd recarbed - one with a full carbo drop, and one with 'the difference' between 1.8 and 2.4 provided via syringe. Both were flat. Dead flat. They've been sitting over 20 degrees for three weeks.

My only thought at this point is that they yeast conked out so hard after dropping from 1091 to 1018, it just had nothing left to carbonate with? Does this even make sense?
 

kelbygreen

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it would more likely be the alcohol content. not sure on the tolerence on the us-05
 

Mr. No-Tip

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it would more likely be the alcohol content. not sure on the tolerence on the us-05
~9.8%. Mate of mine in Brisbane said he brewed a US05 to north of 10% to prove a point...but my US05 could have been in a dubious HBS state...
 

hoppy2B

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Not sure about the whole story, but at 1018 I'm wondering if the yeast ate all the sugar in the brew or if they died with sugar remaining.
You want to be sure all the fermentables have been consumed before adding the carbonation sugar and closing the bottles. Get some SN9 or something like that recommended for restarting stuck ferments. SN9 will go to 18% abv. After adding the yeast and leaving for a couple of weeks to make sure its all fermented out, eg checking with your Hydrometre, then add your carb drops and close them up.
 

kelbygreen

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maybe the yeast you got in the bottle is not viable enough to do any more work? As most people want to get clear beer into the bottles but you are taking out more yeast so it may take longer to carb. Also chilling the yeast then warming it up again must have some effect (if you did chill it).

coopers and I think 90+% of the comercial beers that are naturally carbonated are filted into the bottle then more yeast is added so there is consistency and they know that they are adding viable yeast. Well thats my look at it not sure if its true
 

MHB

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If it has attenuated fully (or further than expected) I think we can safely assume the HBS has nothing what so ever to do with your problem, the yeast has to be healthy to perform as well as it has.
Just had a look at the data sheet and it doesnt give the alcohol tolerance, but if your beer is at 9.8% thats the most likely explanation.
IIRC in one of the linked threads mention was made of planning your brew, choosing your yeast is a very important part of that planning. You have built a wort then chosen a yeast that cant do the job you have asked of it first port of call is to blame your HBS, better to learn how to brew, or at least ask questions before you launch off into new territory.
You could try making up a slurry with a more tolerant yeast (S-33 or T-58), popping the tops and seeding the bottles with a couple of mills of yeast slurry and recapping. Not without its dangers but watch the bottle pressure and refrigerate as soon as you have the desired carbonation level.
Mark
 

kelbygreen

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yeah I looked on fermentis site and no mention of alcohol tolerance but it was the first thing that poped into my head. As Mark said I think your expecting to much out of the yeast it wont attenuate another 77% after the 77.7% it already has done.

Its a real shame as now its a guessing game to how much new yeast will affect the beer, I am looking along the lines of not the taste but the amount of sugar in the original beer and the priming sugar you added as Mark has said it may go over your co2 volumes and may be a risk of bottle bombs
 

Mr. No-Tip

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You have built a wort then chosen a yeast that can't do the job you have asked of it first port of call is to blame your HBS,
Not blaming my HBS at all. Someone in the previous thread referred to the US05 as being in unknown condition/age. That is a fact. I don't know how old it was or how long it was kept in what condition. I brought up that fact again here to query it as a possible explanation. It did well from an attenuation point of view, not so much so from an alcohol point of view (maybe?). You're suggesting that that the attenuation indicated yeast health beyond any issue, so maybe someone cracking 10% with US05 were just lucky. He's an exclusive kegger, so perhaps he too would have found the carbonation issues I am finding now.

As for choosing the 'wrong' yeast... this was a slightly adapted recipe that called for WLP001. I've picked up from reading that US05 and WLP001 are effectively the same yeast (first page google responses refer to them as the same strain). I guess at the finer level this not so - a 3% attenuation difference from the look of it. Lesson learnt.

...As for the various methods to reinvigorate carbonation now...appreciate the input and good info for next time, but I think I'll just decant to PET and force carb when as I want to drink the remaining bottles.

It's a shame, but a good lesson nonetheless. I am sure it would be a cracker beer with a more appropriate yeast. Managed to get a bronze range score in the club comp last week despite serving a flat beer, so I know it's got potential!


For anyone interested, some threads where people claim US05 up to almost 12%:

http://www.homebrewtalk.com/f163/safale-us...lerance-131984/

http://www.tastybrew.com/forum/thread/215370
 

MHB

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Just a couple more points to ponder when talking about yeast
There is the stated attenuation and trick you can use to squeeze a couple of more percent alcohol out of a yeast. By adding some of the fermentables later in the ferment, getting it going in a well aerated wort at a lower gravity gives you a bigger healthier population and having a lower OG puts less stress on the yeast so you get more healthier yeast.
As a rule of thumb I try never to take the gravity back up over the OG
As an example if you were making a big Belgian and decided to add 1Kg of sugar to a 23l wort, that is going to add (1/23*100=4.35oP or 0.0174 points of gravity or 2.3% ABV) so if the OG was 1.080, wait until the SG has fallen to about 1.063 before adding the sugar.
The other point I would like to cover is that its extremely misleading to think any Dry and Liquid yeast are the same, they may have a common ancestor and behave very similarly but that doesnt mean they are the same.
Liquid yeast cultures are true breeding, every generation is the same (bar mutations) but with dry yeast the second generation can be startlingly different to the first, the propagators specially breed the dry yeast so when it is used it tastes/behaves in a certain way upon rehydration and activation, recultured it a couple of times and you are quite likely to get some very unusual behaviour, people then often blame the yeast when in truth US-05 is a lot like 1056 the first time its used, second or third time... dont be too sure. With US-05 the most commonly reported trait is that it wont flock.
Mark

Oh and yes attenuation and alcohol production are linked, an unhealthy yeast wont attenuate well nor will it get up to the stated alcohol tolerance.
M
 

Nick JD

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Pour the bottles into a keg that's been purged with CO2 and carbonate them up and then use a CPBF. Sorted.

I can do this tomorrow for ya if you're on the GC.
 

Mr. No-Tip

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By adding some of the fermentables later in the ferment, getting it going in a well aerated wort at a lower gravity gives you a bigger healthier population and having a lower OG puts less stress on the yeast so you get more healthier yeast.
I think that if I ever do this recipe again (1.091 on braumeister with double mash is a long day!) I will add the 1kg of dex later as you mentioned. Cheers.

Pour the bottles into a keg that's been purged with CO2 and carbonate them up and then use a CPBF. Sorted.

I can do this tomorrow for ya if you're on the GC.
Thanks for the offer. A bit far, but you've reminded me to update my location!
 

kcurnow

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Just another few things to remember with yeast aside from all the other good comments above,
The percentage of fermentable vs unfermentable sugars in the wort will effect the FG
If you use a highly floculant strain that settles early then this can result in a lower attenuation as they settled yeast will not be readily converting the remaining sugars. This will require a longer fermentation time to bring the gravity down to where it should be. (however based on the thread it seems the US-05 has attenuated well so this is not the issue).
Also if you have had the beer sitting in the fermenter for a long time and had a lot of the yeast settle out by bottling time you could have a sufficiently low enough cell count in the bottles that it will take a much longer period of time for the bottles to carbonate than three weeks. And the temperature that you are conditioning your bottles at will effect the yeast activity in relation to carbonation.

cheers

Karl
 

Bizier

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You could try making up a slurry with a more tolerant yeast (S-33 or T-58), popping the tops and seeding the bottles with a couple of mills of yeast slurry and recapping. Not without its dangers but watch the bottle pressure and refrigerate as soon as you have the desired carbonation level.
Mark
If this were me, I would use something like an alc tolerant wine yeast over a lager yeast. One of the dangers which Mark is probably alluding to is that the lager yeast could metabolise sugars which the US05 was unable to. If you used a wine yeast, you can guarantee that it will only eat your priming sugar and nothing left over by the US05.
 

MHB

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The two I mentioned are both Ale yeasts, they are both referenced by Saf as being good for bottle conditioning and restarting stuck ferments, at most they are capable of making an extra percent or so of alcohol. Safer than using something capable of going a lot further.
Mind you another month or two in the bottle might fix the problem without any mucking about.
Mark
 

Ross

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Mr no Tip.

We regularly brew beers above 12% with US-05 & never had a problem with the beer stalling. I'm not sure what the issue is, but US-05 should handle that alc with little problem. Trying a different yeast would probably still be the best bet though.


Cheers ross
 

Yob

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Mr no Tip.

We regularly brew beers above 12% with US-05 & never had a problem with the beer stalling. I'm not sure what the issue is, but US-05 should handle that alc with little problem. Trying a different yeast would probably still be the best bet though.


Cheers ross

Really!? that is in fact good to know.. any special treatment required for that? What have you had it up to Ross?
 

Ross

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12.4%. no special treatment as such, though we generally feed the bigger beers with candi syrup to keep the heat down.


cheers Ross
 

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