Low Attenuated Bock - need suggestions

[rzwahr]

Hi Everyone,
I feel a bit silly posting this but I am not sure what to do since this has never happened to me before. I think I know what the problem is (was) but not sure what to do to "fix" it.

I brewed a Traditional Bock (Jamil's recipe) back on July 28th. OG was 1.075 and I forgot to do a starter night before, so I went the dry yeast route. I used Saflager S-23 and used their recommended rehydration method. Normally I use White Labs or occasionally Wyeast with a 2L or so starter and have never had this problem.

Anyway, to the point, I racked this bock off the yeast today, and was shocked an annoyed that the gravity was 1.026! I was expecting 1.020 max, and was hoping for more in the neighborhood of 1.018ish. This yeast apparently is a ~80-82% attenuator (according to Fermentis). It is also highly flocculent (which could be part of the issue I know). I know there are 3 or 4 probable causes for this which I won't delve into here, but my primary question right now since I am in new territory with this problem is, what the heck to do about it to save my beer.

I tasted the bock and it tastes good EXCEPT the fact that it is sweet for a bock. I wouldn't say cloying, but it's close. This beer would have been perfect had it just attenuated as it should - right bitterness, etc. Dammit, I need to fix this beer.

So right now it's in a glass carboy sitting at 41F for lagering. From what I have read up on so far, it seems that an option would be to raise the temp back into fermenting range and re-pitch a small starter, although I do not know what quantity I should pitch, nor what yeast.

:smack:

Can someone please help me out and help save my fall brew??

-RZ

 

[giraffe]

What were your mash temps? Was there crystal? How long has it been, are you sure its done fermenting, did you raise it for a diacetyl rest at the end of fermentation?

You can certainly try pitching more active yeast from a small starter, but Ive never really had that work, others have. Pitch pretty much any attenuative, alcohol tolerant yeast, and just like a 1L starter.

 

[porterpounder]

You won't need to have a big starter. Just pitch into a cup or so of 1.035 or so wort with a pinch of nutirent to get it to krausen and pitch it into the main batch. Try any attenuative neutral yeast, maybe even S-05 as it won't likely create enough esters to make a difference. Going to have to raise the temp a bit for an ale yeast though, but a good pitch of Cali will work fine in the low 60s.

 

[BrewinHooligan]

You won't need to have a big starter. Just pitch into a cup or so of 1.035 or so wort with a pinch of nutirent to get it to krausen and pitch it into the main batch. Try any attenuative neutral yeast, maybe even S-05 as it won't likely create enough esters to make a difference. Going to have to raise the temp a bit for an ale yeast though, but a good pitch of Cali will work fine in the low 60s.

Exactly this. You should not get any esters or flavor change from adding some us-05 and that should get you down where you want. Also, as mentioned above, always make sure to do a diacetyl rest towards the end of fermentation to make sure any diacetyl is cleaned up and the yeast finishes strong.

 

[rzwahr]

Yep I did do a diacetyl rest of about 48hr at 65F.

I'm thinking maybe a hybrid strain of yeast along the lines of the suggested cali or maybe an alt yeast. Alt yeasts dont really put off too many esters and that is the dead last thing I want in this beer. Thought about maybe some K-97 - my LBS has it in stock and it is a german ale yeast that can run in the low to mid 60's with no issue and it's a high attenuator and has about the same alcohol tolerance as US-05 from what I could find. Thoughts?

Thanks!

RZ