2nd Batch has bad oxidation/cardboard taste

Brewed a cream ale from AHB. Full boil in a new aluminum pot. Pot carefully cooled in <30min in a big tub w/snow. 3wks in carboy, room temp in the dark. 2 wks bottle condition.

Bad bad cardboard taste. Almost undrinkable.
I've read all over this forum and Palmer on oxidation, and cant see where it would've happened. This flavor wont go away with more time in the bottle, right?

My concern is that it will happen again.

My guess would be bubbles at bottling.

Bubbles any time after primary fermentation begins are bad. Splashing during transfer, etc.

It seems early to have such bad oxidation evident. Is it still green?

I was very careful racking to the bottling bucket. No real bubbling.

It tasted like cardboard and a little metallic when I bottled it.

your at risk to oxidize the beer after the alcohol is produced. Did you rack to a secondary? Did your siphon pull air into the beer? Was there foamy air bubbles after racking? How about when you bottled?

I'm not at all sure on this but the new aluminum when bright and shiny will oxidize and become grey or even black. Maybe this had an effect. That's a long shot.

this quote is taken from John Palmers How To Brew

"Do not clean aluminum shiny bright or use bleach to clean an aluminum brewpot because this removes the protective oxides and can result in a metallic taste. This taste-detectable level of aluminum is not hazardous. There is more aluminum in a common antacid tablet than would be present in a batch of beer made in an aluminum pot."

A brand new pot could react similar to a super clean pot.

The pot is the only difference in the brew compared to others.

But, if a new Al pot imparts flavors that are this bad, I would think people would be screaming about it all the time.

triangulum33 said:

The pot is the only difference in the brew compared to others.

But, if a new Al pot imparts flavors that are this bad, I would think people would be screaming about it all the time.

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Well what do you want to hear? If it's not the pot then maybe you F'd up and oxidized everything when you racked the beer.

Perhaps your pot was just extra shiny and clean. I said it was a long shot.

maida7 said:

Well what do you want to hear? If it's not the pot then maybe you F'd up and oxidized everything when you racked the beer.

Perhaps your pot was just extra shiny and clean. I said it was a long shot.

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I'm not arguing with you dude. Just trying to figure this out.

you have to condition the aluminum brewpot before you use it for wort,
boil some water in it for 15-20 min.
this will eliminate any weird taste

My aluminum pot was obviously stamped from sheet aluminum. To do that they use a lubricant. The pot felt oily to the touch. First thing I did was wash with hot water and soap, then boil water for an hour. The boil turned the inside of the pot a dark gray (oxidation I suppose). Then and only then did I use it for a BK.

Not an answer I suppose, but maybe food for thought.

artbrewer said:

you have to condition the aluminum brewpot before you use it for wort,
boil some water in it for 15-20 min.
this will eliminate any weird taste

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+1, fill with tap water and boil until the inside of the pot turns dull and grey. This forms an oxide layer that prevents aluminum from leaching into the acidic wort.

I guess I used beer to season my pot.

Thanks guys.

Well, it's got to better than seasoning with water! That definitley explains the metallic taste.

It should have a clearly visible black-ish coating on the surface once oxidized. This will not scrape off with normal soap and water scrubbing. Make sure it is there before you brew next time!

triangulum33 said:

I guess I used beer to season my pot.

Thanks guys.

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The wort is acidic, so boiling it may not have seasoned your pot. Did it turn a dull dark grey color?

Post fermentation oxidation is probably causing that cardboard taste. Like others stated, when you rack and bottle, make sure you can't see air bubbles swirling your beer around in the racking cane or tubing. This happens to me on every batch am I simply pinch the tube until it catches up with itself and rids the air.

The bottom of the pot has alot of dull blotchy areas. But the sides dont look dull.

I rack from a carboy into a bottling bucket using the "blow into carboy cap" (with sanitary filter) method. Didnt see any bubbles.




Well, I'm going to use best practices, and hope this doesnt happen again.
Thanks!

triangulum33 said:

The bottom of the pot has alot of dull blotchy areas. But the sides dont look dull.

I rack from a carboy into a bottling bucket using the "blow into carboy cap" (with sanitary filter) method. Didnt see any bubbles.




Well, I'm going to use best practices, and hope this doesnt happen again.
Thanks!

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Looks like the metallic taste is probably from your unseasoned aluminum pot, but I'm not sure how you're getting oxygenated. I assume "with sanitary filter" refers to the air blowing in. You're not filtering the wort right?

JuanMoore said:

Looks like the metallic taste is probably from your unseasoned aluminum pot, but I'm not sure how you're getting oxygenated. I assume "with sanitary filter" refers to the air blowing in. You're not filtering the wort right?

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Yes. I bought a little kit that had carboy cap, cane and blow filter. Seems to work really good.

THE POT WAS PRE FERMENTATION NO?

I don't buy the hot side aspect, oxygen is GOOD pre-fermentation.

Cardboard is oxidation.

How long has it been in the bottle?

I am betting it will clear up with age.

Oxidation gets worse.

cheezydemon3 said:

THE POT WAS PRE FERMENTATION NO?

I don't buy the hot side aspect, oxygen is GOOD pre-fermentation.

Cardboard is oxidation.

How long has it been in the bottle?

I am betting it will clear up with age.

Oxidation gets worse.

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agreed. I don't buy that either. There are so many ways to oxidize the beer before bottling. You have to be careful. Maybe, big maybe, your pot is giving a metallic taste. But cardboard is not the pot.