Advice on a wee heavy that stopped sooner than expected

[bnmir]

I did my first partigyle 3 weeks ago (wee heavy & 70 shilling) The wee heavy started at 1.112 after a 156 mash and 90 min boil. I pitched the slurry from a 2l starter of wyeast scottish ale and oxygenated for 45 seconds thru a diffusion stone. I fermented at 68 and it stopped at 1.050 after 2 weeks. I added the yeast cake from the scottish light (smae yeast strain) and this took it down to 1.042 and its been there for a week.
I was hoping for 1.030, its still abit sweet. Any chance of restarting with a high alc tolerant yeast or am I done? Is it safe to add nutrient or 02 this late?
Last alternative would be to blend in a gallon or two of the 70 shilling, which went from 1.052 to 1.020.
Opinions please.

 

[Bensiff]

I'd go with that last alternative. O2 at this point will destroy the beer and you have already slammed it with a massive yeast hit and only got 10 points so more won't likely do anything.

Look at your FG on the 70, only at 1.020 tells you that either you have a serious yeast issue or your wort is not very fermentable. Further, look at your process, high mash temp and long boil both equal lower fermentability. Combine this with what should have been a 3L starter and you were destined to get what you got from the get-go. There is so much grain in high grav beers you don't have to worry about body, it'll be there, you have to worry about being cloyingly sweet. To combat that you need low mash temps and keep the boil time short and intensity low to minimize maillard reactions.

 

[Calder]

I think it's done. Both beers are at 62% attenuation, that should tell you something.

You have 2 things working against you: 1) You used a relatively low attenuating yeast, 70%, and 2) you mashed high reducing your fermentable sugars.

You could probably bring it down a little further if you used a higher attenuating yeast, but it should also have a high alcohol tolerance because you are already over 9%, maybe something like a Belgian strain. Make a starter (maybe a liter), when it is going add some of the beer to the starter (maybe another liter), and when that is going, add it all to the main batch. It worked for me recently on a Barley wine that got stuck at 10%.

 

[bnmir]

I was shooting for a lower og on the wee heavy to be honest. This is my first really big all grain without sugars, and the first 10g batch on a new system, and the first partigyle.
I was expecting 1.030, but in retrospect, that would be on the very high side of the attenuation of that yeast, which wasn't likely with the high mash temp and long boil. All 3 factors do kind of suggest i'm out of fermentables rather than hitting the alc tolerance.
ANy harm in trying to pitch a starter of wlp099?

 

[Calder]

ANy harm in trying to pitch a starter of wlp099?

It won't hurt it and you might get another 5 to 10 points out of it due to it's higher attenuation.

 

[smokinghole]

099 can do some serious work where lower attenuating yeasts leave you wanting. Give it a shot! I just accidentally used 099 in a 1.078 pumpkin ale and it came down to 1.010. That's nearly 90% attenuation in the mid 60s.

 

[bnmir]

Just making a stirplate starter of wlp099 with some nutrient. Planning to pitch the slurry with some sugar and warm up.the wort to 70. I'll keep you posted.

 

[bnmir]

Wow. Wlp099 has taken it another 20pts, and its just slowing down at 1,020.

 

[Calder]

Wow. Wlp099 has taken it another 20pts, and its just slowing down at 1,020.

Wow! I'm impressed!

 

[bnmir]

Its fruity and estery, I hope it cleans up/ages a bit. Definitely not what I wanted back when I started but its drinkable. A learning experience for sure.

 

[TzeentchPlayer]

I have a stuck fermentation myself. I have an AHS Steamroller stout with an OG of 1.091 stall at 1.034 (62% attenuation for WLP 004, 69% is the minimum I'm looking for). I'd like it to be somewhere around 1.018-1.020 since I added 8oz of lactose and a 1% boost. The recipe states the FG should be 1.013.

I ran by AHS today and picked up some yeast nutrient, boiled it, added it to the wort, and gently stirred to rouse the cake. I'm hoping this works. If it doesn't I'll take your route since you've had success with it, but I think I'd use a notty or wlp001 since they are fairly clean yeasts.