Kegged beer too sweet

[shellerb]

After carbonating, should I have to pour off much from the bottom of the keg (settled yeast) before the first "good" glass? I kegged for the second time and it tasted very sweet (and not much carbonation for having been at 12psi/~45 deg for 1 week). I thought based on corrected refractometer readings that it was reasonably attenuated. When kegging, I had cold crashed for a couple of days and didn't notice much yeast being siphoned up. FWIW, it is an Irish Red Ale extract recipe, originally fermented with WY1272. The first time I made this, I thought it was pretty good. I like to think I have gotten a little better after another 5 batches or so.

I pulled it out to let it warm up, added some dry US-05, and pressurized enough to seal the lid in hopes of drying it a bit. Did I do the right thing? Was it just sweetness from the yeast at the bottom of the keg?

Thanks for any advice.

 

[Euphist]

I've never noticed the settled yeast tasting sweet...just yeasty. It might not have been done fermenting (be glad it's in a keg and not bottles.) If you're brewing AG, it could also be a mash problem but with extract, it pretty much has to be a fermentation issue.

Depending on how much there is left to ferment, you may need to vent some pressure as you go, but IMO the adding of the yeast certainly can't hurt anything...

 

[shellerb]

Thanks. I didn't think it should be sweet if it was settled yeast but read that from another website. That site also says that a lack of carbonation can change the perceived sweetness also.

Hopefully, it finishes fermenting in the keg.

 

[n240sxguy]

Just out of curiosity, why did you add yeast when you kegged it?

 

[shellerb]

I added more yeast after kegging, carbing, waiting a week, and pouring the first sweet glass. I thought it would help finish fermenting it.

 

[n240sxguy]

Oh, I gotcha now. I thought you added the yeast when you first kegged it.

 

[Coff]

What was the corrected refractometer reading? And now that the beer is degassed try taking a reading with a hydrometer to be sure its fully attenuated.

I dont trust those corrected refractometer readings, unless of course I am doing something wrong, sometimes its spot on and some times its way off for me. I try it just about every time I take a hydro reading, too inconsistent for me.

 

[shellerb]

It sat at 12 psi for a week. I opened the keg but wouldn't it still have a lot of dissolved CO2? How does that affect the hydrometer/refractometer readings?

I'm not completely trusting of the absolute refractometer measurements but assume that a stable reading over a few days would still be indicative of either a finished or stalled fermentation. Since the first "corrected" reading was about the correct apparent attenuation, I assumed it was done, waited another couple days and started the cold crash.

I hope that being in the keg it is at least a little more correctable than if it was bottled.

 

[shellerb]

The original and final gravity readings were 1.051 and 1.025, respectively. After correction (according to the spreadsheet at (http://seanterrill.com/2012/01/06/refractometer-calculator/), after correction, the FG is about 1.0122 for an apparent attenuation of 75.2%. WY1272 should have an attenuation range of 72-76%. So, I thought I was done. The quoted values are APPARENT attenuation, right, not actual attenuation? BeerSmith also says that the FG should be about 1.013.

 

[Yooper]

The original and final gravity readings were 1.051 and 1.025, respectively. After correction (according to the spreadsheet at (http://seanterrill.com/2012/01/06/refractometer-calculator/), after correction, the FG is about 1.0122 for an apparent attenuation of 75.2%. WY1272 should have an attenuation range of 72-76%. So, I thought I was done. The quoted values are APPARENT attenuation, right, not actual attenuation? BeerSmith also says that the FG should be about 1.013.

With a refractometer, it's hard to say what the actual FG was. I'd check it with a hydrometer.

Not much you can do now that the beer is kegged, though.

 

[shellerb]

Are you saying that warming back up and re-pitching in the keg is unlikely to restart fermentation and dry up the beer?

Also, are Wyeast/White Labs attenuation numbers for various strains apparent or real attenuation values?

 

[Yooper]

Are you saying that warming back up and re-pitching in the keg is unlikely to restart fermentation and dry up the beer?

Also, are Wyeast/White Labs attenuation numbers for various strains apparent or real attenuation values?

Repitching is very unlikely to restart fermentation, as the alcohol in the beer will make an inhospitable environment to a new yeast (alcohol is toxic to yeast). A gradual acclimation works when you first pitch, but repitching just some yeast means that the yeast will die before reproducing and fermenting in most cases. You could repitch by pitching on an active yeast cake, but that's probably not a very viable option once the beer has been kegged.

The give the apparent attenuation % values.

 

[mrshaund]

did you let it ferment for the full 4 weeks, it seems like fermentation may have fudged. It looks like your estimated FG should have been 1.010-1.014. Also I could be wrong but for the slow carb route I think you would want 2 weeks at 12 psi to achieve 2.26 volume, I could be completely wrong on that though.