Harvest Ale Sourness

[TheMattTrain]

Hey folks,

I'm trying to figure out where I'm getting a sour flavor from. I'm not sure it's sour per-se, but that's the only way I can describe the flavor right now. I'm going to post my recipe below then explain the process to see if anyone has any thoughts.

Maris Otter Pale (UK) 8.0 lb
Munich Light (CA) 1.5 lb
American Vienna 1.5 lb
Flaked Oats 0.5 lb
CaraMunich I (DE) 0.5 lb
Carafa I (DE) 1.0 oz

Tettnanger 1.0 oz 60 min
Saaz 0.5 oz 15 min
Hallertau 0.5 oz 15 min

Wyeast 1007, German Ale

I used whole leaf hops for the first time. I brewed as I usually do,all grain, hit my numbers pretty close if not dead on (can't remember and I'm not looking at my notes). The fermentation kicked off within 48 hours using 1 smack pack of yeast.

Fermentation held between 66-72 degrees, the bulk of which was down around 68.

Beer sat on the yeast cake for about 5-6 weeks. I noticed at one point it got a second krausen. Gravity check before the second krausen showed it slightly high on FG, it finished slightly below target FG.

I kegged the beer as usual. I'm diligent about sanitation throughout the process. Only issue on this was that I overfilled the keg. I put my cleaned/sanetized lid on then forced CO2 in about 2-3 hours later (my tank ran dry and I didn't notice until I went to force crab... had to go get a fill). It's been in the keg for a little over a week, just did my first draw.

The only thing I can think is that I got too much trub on this first pull and it will eventually clear out and taste fine.

Any thoughts? Do any of my grains, malt, or yeast, give it a slightly tangy flavor that I'm getting? Any insight would be appreciated.

FWIW, I've never had an infection *knock wood.* I've been brewing all grain since Jan 1 2014.

 

[Yooper]

72 degrees during active fermentation can cause some "fruitiness". Is that possibly what you're tasting? Green apple, pear, banana?

Here's the description from Wyeast on that strain:
A true top cropping yeast with low ester formation and a broad temperature range. Fermentation at higher temperatures may produce mild fruitiness. This powdery strain results in yeast that remains in suspension post fermentation. Beers mature rapidly, even when cold fermentation is used. Low or no detectable diacetyl.

Origin:
Flocculation: low
Attenuation: 73-77%
Temperature Range: 55-68° F (13-20° C)
Alcohol Tolerance: approximately 11% ABV

___________________________________________________

What concerns me is the lengthy time in the fermenter, if you got a second krausen. Generally the beer finishes up, and doesn't form another krausen unless an infection process is happening.

 

[TheMattTrain]

I'll have to taste it again to see if I'm getting any of those. Green apple might be a good description. I'm not sure it ever saw much above 70 to be honest... I'm sort of a lazy brewer when it comes to fermentation. Most of my stuff stays in the mid to upper 60's, even during active fermentation. My brews sit on the cement floor of my basement, which at this time of year is very cool.

Gonna keep hoping it was trub giving it a weird flavor and maybe it's better than I thought. I really don't think it's infected, though. It sat in primary for 5-6 weeks and never showed any signs of infection except for that weird second krausening.

 

[Yooper]

Another thing to consider is that many people find that some yeast flavors include "tartness", and 6 weeks on the trub would definitely impart plenty of yeast flavor.

 

[TheMattTrain]

Thanks for sticking with me here, Yooper!

I'm having another taste today. It poured a little oddly... very big bubbles today which eventually died down into a soft head which dissipated quickly down to a fine layer over the surface of the beer in a pint glass.

I'm getting a really light bodied beer which isn't what I was going for. I didn't keep great notes because I was brewing with a friend, but I'm pretty sure I mashed around 152 for 60 mins then mashed out at 170 for 15 mins.

The beer is VERY hazy, probably from the low flocculating yeast. It tastes less sour today, but still has that scent. It's almost lemony. I wouldn't call it sour apple.

I'm going to say it's probably just that it sat on the yeast too long and gave it some yeasty flavors. Is that something that would age out?

 

[Yooper]

I'm going to say it's probably just that it sat on the yeast too long and gave it some yeasty flavors. Is that something that would age out?

No. That's why I only do 14-20 days in primary, sometimes less as I don't care for the yeast character imparted by a long contact time with the trub. Others do, and will purposely leave the beer in the primary for a month to get that character.

It may be an infection process, though, if the beer is thin and not great tasting. If it gets worse, it's an infection. That's about all the advice I have, sorry to say.

 

[TheMattTrain]

Thanks the advice, Yooper. I'm going to see if I can get my buddy over who is a more experienced taster to take a sample and see what he thinks it might be. I'm very torn about it only because I've never had an infected batch and there were no signs of infection other than that second krausen that popped up.

Do you happen to know what type of bug could cause something like that?