high FG with high OG beer

This has been my first attempt at a high gravity beer. The brewing process went smoothly but after 4 weeks my gravity has only dropped to 1.040. The OG was 1.090. I pitched with with Irish Ale yeast and a Nottingham Ale Dry yeast because of the high OG. I at 3 weeks it was 1.042 and I added yeast nutrient and more nottingham ale yeast and raised the temperature. I tasted it and it still tastes sweet; obviously there is still a lot of fermentables in there.

Will the gravity drop with time? What is a reasonable FG for this beer?


BeerSmith Recipe Printout - www.beersmith.com
Recipe: Oat Meal Stout
Brewer: Damon Houghton
Asst Brewer: none
Style: Russian Imperial Stout
TYPE: All Grain
Taste: (35.0)

Recipe Specifications
--------------------------
Batch Size: 5.50 gal
Boil Size: 6.99 gal
Estimated OG: 1.090 SG
Estimated Color: 47.3 SRM
Estimated IBU: 59.6 IBU
Brewhouse Efficiency: 75.00 %
Boil Time: 120 Minutes

Ingredients:
------------
Amount Item Type % or IBU
0.36 lb Light Dry Extract (8.0 SRM) Dry Extract 1.95 %
15.00 lb Pale Malt (2 Row) US (2.0 SRM) Grain 81.08 %
1.00 lb Oats, Flaked (1.0 SRM) Grain 5.41 %
0.95 lb Roasted Barley (300.0 SRM) Grain 5.14 %
0.75 lb Black (Patent) Malt (500.0 SRM) Grain 4.05 %
0.44 lb Chocolate Malt (350.0 SRM) Grain 2.38 %
1.00 oz Magnum [13.60 %] (90 min) Hops 37.8 IBU
1.50 oz Goldings, East Kent [5.00 %] (30 min) Hops 15.0 IBU
1.00 oz Fuggles [4.00 %] (20 min) Hops 6.3 IBU
0.50 oz Fuggles [4.00 %] (2 min) Hops 0.4 IBU
1 Pkgs Irish Ale (Wyeast Labs #1084) Yeast-Ale
1 Pkgs Nottingham (Danstar #-) Yeast-Ale


Mash Schedule: Single Infusion, Full Body, Batch Sparge
Total Grain Weight: 18.14 lb
----------------------------
Single Infusion, Full Body, Batch Sparge
Step Time Name Description Step Temp
45 min Mash In Add 22.68 qt of water at 170.5 F 158.0 F

what is the temperature?

Have you been swirling the fermenter occassionally to keep the yeast in suspension?

Sometimes you need to reuse a yeast cake from a previous batch for a beer with so much sugar. You could also make a big starter, add some yeast nutrients, keep it on the high end of the fermentation range (typically around 70 for ale yeasts), and aerate it very well to help it along as much as possible.

The temp was about 65 before I raised it. It got up to 68 for that 4th week. I swirled it and got it aerated right after I pitched, but I was out of town for the next 2 weeks. After the third week I stirred it vigorously when I repitched .

ski36t said:

The temp was about 65 before I raised it. It got up to 68 for that 4th week. I swirled it and got it aerated right after I pitched, but I was out of town for the next 2 weeks. After the third week I stirred it vigorously when I repitched .

Click to expand...

The two weeks you were gone is when you would need the swirling the most. I had a couple of 1.070 brews that I would swirl every few days, which got them both to 1.019'ish.

Careful with that vigorous stirring you don't want to oxygenate the brew, just get the yeast back up into the brew.

Is there any possibility that what is left is all unfermentable? Is it ok to just put it in the secondary and wait it out while maintaining a higher temperature?

Any suggestions?

Give it a gentle rouse every day and check the gravity again in a week. It sounds like your gravity is still dropping, but slowly. Right now sounds like a very bad time to rack. You only have about 55% apparent attentuation right now, so I doubt everything left in there is unfermentable. You'll just have to keep your yeast going.


TL