RIS has gone south...why?

[prrriiide]

We brewed a 10g AG RIS back in November:

Recipe Specifications
--------------------------
Batch Size: 10.00 gal
Boil Size: 11.49 gal
Estimated OG: 1.102 SG
Estimated Color: 66.4 SRM
Estimated IBU: 87.2 IBU
Brewhouse Efficiency: 60.00 %
Boil Time: 60 Minutes

Ingredients:
------------
Amount Item Type % or IBU
40 lbs Pale Malt (2 Row) US (1.5 SRM) Grain 81.47 %
5 lbs Roasted Barley (300.0 SRM) Grain 10.18 %
1 lbs Black (Patent) Malt (500.0 SRM) Grain 2.04 %
1 lbs Caramel/Crystal Malt - 60L (60.0 SRM) Grain 2.04 %
1 lbs Chocolate Malt (350.0 SRM) Grain 2.04 %
9.6 oz Oats, Flaked (1.0 SRM) Grain 1.22 %
8.0 oz Special B Malt (118.0 SRM) Grain 1.02 %
4.00 oz Magnum [14.00 %] (60 min) Hops 65.2 IBU
3.00 oz Williamette [5.40 %] (30 min) Hops 14.5 IBU
1.00 oz Simcoe [13.00 %] (15 min) Hops 7.5 IBU
8 Pkgs Tennessee Whiskey (White Labs #WLP050) [StYeast-Ale


Mash Schedule: Temperature Mash, 1 Step, Full Body
Total Grain Weight: 49.10 lb
----------------------------
Temperature Mash, 1 Step, Full Body
Step Time Name Description Step Temp
40 min Saccharification Add 61.38 qt of water at 171.2 F 156.0 F
10 min Mash Out Heat to 168.0 F over 10 min 168.0 F


This was our first stab at a HG beer like an RIS. Our IPA usually comes out around 8%, and most of the beers we brew come out north of 7%. But this was a different beast. Samples have been taken at several points throughout the "getting happy" of this beer in the kegs, un-carbonated - but purged. All have tasted unbelievably good. Full-bodied, roasty, just a great stout flavor, with little alcohol heat and little sweetness. All of these samples have been un-filtered and un-carbonated. We filtered the beer 2 weeks ago and put it back in the kegs.Yesterday, I put about 12 oz. in a plastic water bottle and carbed it with a Carbonator fitting. The carb looked great, but when we tasted it, it tasted like something you'd pour over your pancakes. Sickeningly sweet. Almost un-drinkably sweet. A revolting development in a beer that held such promise only a short couple of weeks ago.

The OG was 1.098. Measured grav on 6/13 was 1.020. It's now at 1.028. Is it normal for it to come back up?

Why is our RIS so sweet now that it's been filtered? Was the yeast tempering the sweetness?

I'm wondering...should I drop some champagne yeast or other high-grav yeast in there to see if it will finish (as if the whiskey yeast wasn't enough...) down to a drier, more drinkable state?

I'm feeling bummed, because two months ago, this tasted like a best-of-show beer.

 

[Gameface]

I'm curious why, after so much time aging, you decided to filter a stout? Do you filter frequently? Did you possibly oxidize the beer during filtering?

 

[prrriiide]

We filter most everything unless it is crystal clear coming out of cold crash. A very experienced local brewer tasted it and couldn't nail down any off-flavors other than excessive sweetness. It doesn't taste oxidized to me, either. Also, my filtering process is very hostile to oxygen introduction. I assemble the filter in star San, and push through purged kegs with co2.

 

[aStoutObserver]

Have you calibrated your hydrometer to make sure it wasn't that? Or adjusted for temperature? The 1.020 could have been wrong?

 

[prrriiide]

Yes, temp adjusted and hydro is correct.

 

[wingedcoyote]

It's normal for a high-grav beer to taste sweeter over time, because hop bitterness fades while malt sweetness does not. But for it to taste a LOT sweeter all of a sudden is indeed very odd. Sorry to hear that happened to such a special beer, that sucks.

 

[Piratwolf]

My first thought is that filtering can remove very small hop bits and yeast covered with hop oils that provide balancing bitterness. That would add the perception of sweetness.

However, I don't believe it's possible for the gravity to go up without adding something. Must have been an error on the first or the second measurement somehow.


Sent from my iPad using Home Brew

 

[aStoutObserver]

Edit - never mind

 

[prrriiide]

So can I fix it? My thought is to do a ½ gallon, ½ hour mini brew of an oz of Magnum, and steep a pound or so of roasted barley once the temp drops below 155. Chill and put into the beer. Thoughts?