Can boiling in certain keggles cause off flavors in final beer?

[ParanoidAndroid]

I've brewed over 10 batches of beer that have been dumped. Thats 1.5 years of brewing for me. I've made a few threads on it, so I wont go into finer details. I started out with a three vessel system and batch sparging. I'm now doing BIAB in a single vessel because I wanted to cut down on variables. The off taste was hard to knock down, but it was terrible; almost a combination of all the off flavors.

The reason I ask is I just brewed a SMaSH IPA in my old 4 gallon pot and it actually tastes decent and is drinkable; nothing like the others. I tried anything and everything to pinpoint the cause of the off flavor, and the only constants every time were the keggle that was used, and the copper immersion chiller (I even pre-boiled the chiller one time to make sure that wasn't it). I didn't use the chiller on the SMaSH and the recipe was just a scaled down 5 gallon BIAB.

Is there a certain keg that is not suitable for boiling in?


Things I do:

-Use 100% RO water and use EZ water for mineral/acid addition (so not a water problem)
-Use Ph meter and calibrate every time (so not a mash ph problem)
-Use Thermapen, which is the most accurate therm you can buy (so not a mash temp prob)
-Run through mill twice (getting 75% eff)
-Dedicated ferm chamber with thermowell that sits in wort (so not a ferm temp problem)
-Use yeast calcs (so not an underpitch problem)

I've also dismantled and cleaned/disinfected all fittings, use a sump pump in ice to get to pitching temp quickly, ferment on lower end of range,

 

[giraffe]

Have you ruled out infections?

Is the keg steel? Are there any other fittings below the boil line, If so, what metal are those?

 

[douglasbarbin]

Have you tried washing and rinsing the keggle and immersion cooler really well?

 

[GotPushrods]

Have you taken some beer to your LHBS to get some opinions on how to describe the off-flavors? We all love speculating about brewing here, but this thread could get to be a pretty huge multi-page snipe hunt without SOME hint as to the direction to start looking.

Just as a start, check out this flavor wheel and see if there are any off-flavors you can match with descriptions.

 

[acidrain]

Why do you think it's the keggle and not the chiller?
Is the chiller bright copper colored when you use it?

 

[ParanoidAndroid]

Have you ruled out infections?

Is the keg steel? Are there any other fittings below the boil line, If so, what metal are those?

Looks like a normal AB keg. I'll attach some pics in another post.

I would like to think I ruled out infections, but its always a possibility. I purchased new Starsan thinking it might have been bad. I use distilled water when mixing it.

Ive taken apart all fittings (all are from BobbyM's BrewHardware site) and soaked in Oxyclean, then sprayed with starsan then reattached. I sprayed starsan on outspout after boiling and before running to fermenter.

Have you tried washing and rinsing the keggle and immersion cooler really well?

I boiled the IC before brewing one time. The rest of the time I just rinse really well. Its discolored beforehand, but shiny after boiling. From what I read on here, that was normal.

The keggle I wash with Brewers Friend powder and use the green scrubby pads. I rinse thoroughly.

Have you taken some beer to your LHBS to get some opinions on how to describe the off-flavors? We all love speculating about brewing here, but this thread could get to be a pretty huge multi-page snipe hunt without SOME hint as to the direction to start looking.

Just as a start, check out this flavor wheel and see if there are any off-flavors you can match with descriptions.

Musty, couple of sours, alcoholic on one batch, tart.

I wish "Asswater" was an option on that chart. That would explain most.

BTW thanks for that. I havent seen that off flavor chart yet.

Why do you think it's the keggle and not the chiller?
Is the chiller bright copper colored when you use it?

The chiller is possible. Ive had it for years and think it came from midwest (maybe 2005-6).

 

[GotPushrods]

Musty, couple of sours, alcoholic on one batch, tart.

I wish "Asswater" was an option on that chart. That would explain most.

BTW thanks for that. I havent seen that off flavor chart yet.

Sour, tart, and let's just throw in asswater... all point to infection.

About 10 years ago when I started brewing, I mistook plastic/chemically for infection. It was chlorophenols. I've been de-chlorinating with Campden almost since I started brewing, it can be downright nasty.

But let's assume it is infection. You are boiling the keggle. You'd need to look at everything after that. An immersion chiller is a lot less likely candidate than in internally flowing CFC or plate chiller.

Do your fermentors have any fine scratches on the inside?

What is your process for making a starter? Boiled in a flask?

Imagine you're at flameout -- go through every step in your mind and everything that touches the wort from there until your glass. This all assumes infection but it's a start.

 

[douglasbarbin]

Agree that the off-flavors described all point to infection.

 

[ParanoidAndroid]

Here the pics of keggle.

 

[GotPushrods]

If there is nothing obvious soon, your best bet might just be to replace all the plastic equipment that touches post boil wort (hoses, buckets, etc), use a new bucket and sprinkle in some dry yeast. Try this for a few batches and see what happens. You can boil silicone, but all the vinyl/pvc/hdpe/pet should probably not be used for a while and see how it goes.

 

[ParanoidAndroid]

If there is nothing obvious soon, your best bet might just be to replace all the plastic equipment that touches post boil wort (hoses, buckets, etc), use a new bucket and sprinkle in some dry yeast. Try this for a few batches and see what happens. You can boil silicone, but all the vinyl/pvc/hdpe/pet should probably not be used for a while and see how it goes.

How often do Better Bottles last?

Ive had a few for a while. One has a dent in it.

Are these recyclable at any recycling place?

 

[rekoob]

Nice keggle.

I have to agree that it sounds like an infection.

I would give the valves a good look and maybe clean/soak in some starsan. I really don't see the keggle or the IC being your issue.

After that I would agree with any tubing or plastic has to come out of the equation.

If you have silicone tubing and it's pretty used, maybe remove the QD's from them, boil them, trim the ends, and put the QD back on.

Good luck and keep us posted.

 

[GotPushrods]

How often do Better Bottles last?

Ive had a few for a while. One has a dent in it.

Are these recyclable at any recycling place?

They are perfectly recyclable, but should last forever with a little care.

MoreBeer also sells some smooth-sided PET carboys which I love. (Still wish they offered a 6.5 gallon though ) And there's always the good 'ol Ale Pail for cheap.

Clean them with a warm percarbonate-based soaking and avoid scratching the inside by scrubbing. Shake up a gallon of StarSan to sanitize and plastic will last virtually forever.

I still don't think you're kettle is an issue since you boil in it, but it's not the worst idea to take off the ball valves and boil them with any silicone you have. Easy insurance.

 

[ParanoidAndroid]

OK, so I have been reading up on cleaning and sanitizing Better Bottles. I have been using a carboy brush for every cleaning. I saw where that is not recommended due to possibly scratching. I'm not that careful either. I assume its infections caused by scratches in the plastic? Such a damn rookie mistake if this is the case.

 

[giraffe]

Scratches in plastic are very hard to sanitize, bacteria can usually survive deep in the scratches during sanitation. If the plastic is scratched, replace it. Im guessing your IPA was ok, cause it was so heavily hopped it inhibited bacterial growth not because of the keggle.

 

[afro_lou]

I'd agree with all of the above. The safest thing to do would be to just replace all your tubing (except the silicone, as mentioned above) and pick up a new fermenter.
I can't see how the keggle would be causing these off flavors, unless the wort is getting majorly scorched. Which seems unlikely...

 

[gotbags-10]

What are your FG readings? I was having problems with infections and mine were always real low. Like .999-1.002

 

[ParanoidAndroid]

Hmm, seems like Better Bottles are having production issues. I was about to order some more, and everywhere is out of stock.

 

[Psylocide]

Glass doesn't scratch like that, always an option.

Either that or buy yourself a bucket fermenter for ~14 bucks and try that.

 

[douglasbarbin]

Glass doesn't scratch like that, always an option.

Either that or buy yourself a bucket fermenter for ~14 bucks and try that.

Or a stainless fermenter if you want to go upscale.

 

[jekeane]

before spending a lot of cash I would get a simple bucket fermenter. Replace your plastics post boil and see how that batch turns out.
So from the boil kettle clean the valve replace the hose to the fermenter, use a new bucket and airlock, replace whatever your using to get a sample.