Off flavor after fermentation but not before

[opalko]

Very frustrated! I can't seem to avoid a grainy/corny flavor that happens after fermentation. I was meticulous in my brewing but when I went to check final gravity yesterday before bottling, ugh. The bad thing is before pitching yeast when I check the OG the stuff tasted great..malty, slight hops - wonderful!
My recipe (ordinary bitter - 2.5 gallons BIAB): (US units)
3 lbs Maris Otter
3 oz 40L crystal
1/2 oz EKG 60 mins
1/4 oz Fuggles 15
1/4 oz EKG 5
1/4 tablet Whirlflock 5 mins
4 gallons water strike temp 156F
Mash in at 152
Temp check 149 at 20 minutes, high heat 30 seconds
Regular stir at 15 minute intervals
Ended 3.9 gallons pre-boil
60 minutes HARD boil
Finish with 3.2 gallons, ice bath cool (not covered!) to 60F in about 4 hours.
Pitched Munton Dry (regular), OG 1033 - tastes GREAT
2 weeks later, FG 1010
Corny, grainy taste, not sure best way to describe...doesn't taste like before fermentation.
This happens nearly every time I brew. I sanitize with StarSan.
What am I missing? I nearly always use dry yeast alternating between Nottingham, S-04, or Muntons. I have one package of WLP002 English Ale that I thought I would give a last go with.
Help!
Cheers
Opalko

 

[wilserbrewer]

I think you need to give your beer more time....sampling out of the fermenter is tricky business. I think you need another 3-4 weeks until reporting off flavors....your beer is far from mature and harsh flavors are not unusual. All the sugar before fermentation masks the stronger flavors.
Rdwhahb

 

[opalko]

How long do you recommend for single stage fermentation for a simple english ale?

 

[wilserbrewer]

How long do you recommend for single stage fermentation for a simple english ale?

Point taken....water perhaps?
Sorry not much help....

 

[CA_Mouse]

What is your fermentation temperature? What are you using to control your temps? Most English yeasts I've used seem to do best at 64*-66*F and after fermentation slows down letting it rise to 68*F to finish off the last couple of points and let the yeast clean up after themselves.

 

[opalko]

60-62 with a temp controller

 

[meatcleaver]

so, this is a recurring issue (multiple batches)?
does it get better with bottle conditioning? (or do you keg?)
I agree you could try ramping up ferm temperature at the end to help the yeast clean up but a grainy taste? makes me think stale grains but if it tastes good on brew day I dunno.

 

[NatureOfTheYeast]

Your corn/grainy off flavor is consistent with DMS.

Do you cover your pot at any point during the boil? DMS will volatilize and condense on a lid, and drip back into the kettle, being stuck forever.

Not sure if that's what's going on, but if your kettle is uncovered at all times during the boil (during cooling is okay, I cover my cooling kettle and have no DMS), then I'd rather wait until it's in the bottle/keg for a while before really judging the beer.

I've had some really nasty, and also fleetingly awesome, flavors from the fermenter.

Some grain lots just have more SMM (precursor to DMS) in them due to agricultural variation. Maybe try a 90 minute boil?

It might also be a diacetyl producing wild bacteria like pediococcus, but that also makes lactic acid, which is tart, mildly lemony, and hard to miss, so I don't think it's that. The Star-San would also slap that down pretty readily, unless you're playing it fast and loose, which I have no reason to believe.

One last thing that I can think of on the diacetyl front, is from the English strains being fermented so low (60-62 is quite low for a British yeast). The yeast might be flocculating too early and not getting a chance to clean up after itself.

Most importantly, when did this problem start? Has it always been there or is it new?

 

[madscientist451]

Four things to try.
- Start your fermentation in the low 60's, 62-64 is ok, after 3-4 days, (after the fermentation kicks off) ramp it up to about 72, and let it finish.
-Use the Liquid yeast you have, the 002.
(note, you can re-pitch the yeast several times)
-If you are using tap (city or well) water, try using bottled spring water instead.
-Do a DMS test: pull a sample after fermentation is complete, put in microwave and heat to 140F and see if you can smell any cooked corn.
There are many other things to try, but its best to keep things simple when trying to solve a re-occurring problem.

 

[opalko]

No, never covered furing boil.

 

[Yooper]

Have you tried a batch with distilled or reverse osmosis water, to rule out water issues?

 

[opalko]

No, using ro water is for my next attempt, maybe today!

 

[opalko]

I was going to use this water, but the pH seems very high?...
http://www.nestle-watersna.com/asset-library/Documents/PL_ENG.pdf

 

[TexasWine]

I was going to use this water, but the pH seems very high?...
http://www.nestle-watersna.com/asset-library/Documents/PL_ENG.pdf

pH of the water doesn't matter so much. But, the pH of the mash does, which is impacted greatly by the water's alkalinity.