EXTREMELY High FG On My Imperial Milk Stout

[WhitePaw]

Okay, here it goes. I've taken a stab at making an imperial milk Stout and was shooting for a full bodied beer at 12.1 percent.

I'm super OCD about measurements, temps, ingredients, etc. But now I have a beer that started with an OG of 1.115 and an EXPECTED FG of 1.025. However after 2 weeks in the primary my gravity is stuck at 1.044. I know this is MUCH higher than expected - even accounting for the lactose addition. This is my recipe:

14 lbs pale malt
1.5 lb crystal 60
1.5 lb biscuit
1.25 lb chocolate malt
12 oz black patent

2 lb lactose (added 10 minutes before ends of boil)

Pitched with 2 smack packs of Wyeast Scottish Ale

I mashed at 154 degrees for 1 hour. Standard 60 minute boil.

I've done a ton of research and have ruled out the Beersmith issue with lactose sugar calculations, etc. However all postings here state I should be nowhere NEAR as high as the 1.040's for FG - even when accounting for a 14 point gain in gravity for a 5 gallon batch with 2 lbs of lactose.

Fermentation was vigorous and took off in 12 -18 hours. Went strong for about 2 days - even putting well to use my blowoff tube rigging. Then a gradual slowing for 3 days to a near standstill.

At 7 days my gravity was 1.045. At 11 days I'm still sitting at 1.044.

Any ideas? What are my next steps??? Do I pitch more yeast? Let it sit another 2 weeks? (Even though the gravity has stabilized?)

I wanted to rack to a secondary over cocoa nibs prior to bottling but I'm now at a loss as to whether that's even an option at this point.

Any help is greatly appreciated!!!

 

[W0rthog]

How did you aerate the wort?

 

[Kent88]

Mostly replying to sub the thread, but I'd say rack onto the nibs and let it sit. If you happen to be brewing with that same yeast soon, make a yeast starter and put a portion of that in the secondary fermenter the day before you rack into it (or would this introduce to much oxygen?).

 

[W0rthog]

I would let it ride or perhaps choose a yeast that has better attenuation to chew through the rest.

 

[afro_lou]

A few questions:
Fermentation temp? Was it stabilized (ie fermentation chamber)?
What are you measuring the gravity with? Hydrometer or Refractometer?

It may be an unfortunate stuck fermentation, in which case a little swirl of the fermentor might get things going. But you may need to pitch more yeast if that doesn't do the trick.

 

[stpug]

You're basically 9% away from the low end AVERAGE apparent attenuation for that yeast strain.

Your grist contains 2 pounds of nearly unfermentable complex sugars (roast malt).

You also have 1.5 pounds of moderate attenuation sugars (crystal).

You also have 2 pounds of completely unfermentable sugars (lactose).

Last, you mashed the entire grist in the "moderate dextrin" range.

I guess what I'm saying is that it's totally understandable that your attenuation is well below the average range.

There's a pretty good possibility that a large starter of high attenuation lager yeast fermented in ale range would bring that gravity down a fair bit. Build up a large 2 liter starter; when it's finishing up after a day or two, put it in your secondary; shake it well to re-aerate; after aeration, rack your on to it and let it do it's thing. Lager yeast has the most potential to ferment complex sugars, however you'll need it to be high attenuation and high gravity. There are several other strains that would probably work as well, it'll just be a matter of nailing one down.

 

[afro_lou]

[emoji115]that's a much better answer[emoji115]