Persistent oxidised beer problem

[Seeker]

Boil is for 90 minutes with 15-20 rest after flame out.

Interesting about hot transfer splashing. I'd read somewhere that it's not a problem due to near boiling liquid not absorbing oxygen.

I'll avoid from now on, thanks

 

[dicko]

When I no chill I inject a bit of Co2 into the bottom of the cube and transfer wort through a silicon hose.
I also run the wort very slowly for the first few litres and tilt the cube towards the hose end so as the wort coming into the cube is discharging under the surface as soon as is possible.

 

[TheWiggman]

I used to splash my hot wort into the fermenter on my first few brews because I thought I was doing the right thing, and I got a 'character' from the beer I'd rather not have that was similar to oxidation. Try avoiding any splashing on your next brew with a known recipe and see how you go.
As you said, the fact the FWK tasted fine and your brew didn't alludes to your ingredients or process being at fault.

 

[Seeker]

Thanks guys.

I might actually kettle chill the next one to rule out any possibility of oxidation during transfer - I need it straight in a fermenter anyway.

 

[manticle]

Not as easy. You can't just get your hand in there to give them a wipe.

I won't say one is easier than the other but if you rinse your cube immediately on emptying then put enough boiling percarb solution in so that the krausen ring is submerged when the cube is upside down, you have no need to scrub/wipe. Usually 2-3 litres and a quick shake does it for me but you can turn it upside down and just leave for a few hours or overnight if not in a rush. If you're one of those people who leaves their fermenting vessel to develop krausen crust then it becomes more difficult (not impossible).

 

[Nick667]

I used to splash my hot wort into the fermenter on my first few brews because I thought I was doing the right thing, and I got a 'character' from the beer I'd rather not have that was similar to oxidation. Try avoiding any splashing on your next brew with a known recipe and see how you go.
As you said, the fact the FWK tasted fine and your brew didn't alludes to your ingredients or process being at fault.

You did well.
I didn't figure it out for years. Just recently in fact.
Palmers online book has it hiding there under 'Metallic' in off flavours. Aerating over 26C is a no no.
I thought I was doing the right thing as well.
There must be hundreds of home brewers falling for the trap and getting that nasty homebrew taste.
I all grain now but when I used to kit and kilo I, and most others, would throw that water in there.

 

[Jack of all biers]

Palmers online book has it hiding there under 'Metallic' in off flavours. Aerating over 26C is a no no.

Read again. From Palmers 'online book' under the chapter 7 'Boiling and cooling'

'7.4 Cooling the Wort

At the end of the boil, it is important to cool the wort quickly. While it is still hot, (above 140°F) bacteria and wild yeasts are inhibited. But it is very susceptible to oxidation damage as it cools.'

And in the next paragraph;

'Minimize splashing to avoid oxidation.'


EDIT - Okay, now you can call me finicky. The only reference to metallic in off flavours (or anywhere else) in Palmers brew manual is in reference to metal oxides, not oxidation. Huge difference.

 

[Jack of all biers]

I'd read somewhere that it's not a problem due to near boiling liquid not absorbing oxygen.

This is kind of right in that O2 (oxygen) won't absorb into the liquid via suspension. However the oxygen molecules are easily bonded to other chains at the high temperatures of the hot wort and form various oxide chains (which is the process of oxidation). These oxide chains can later break down chemically and thereby cause the off flavours and other problems (ie staling of the beer).

The difference between O2 suspension (aeration) and oxidation (O2 spliting to form oxides with other molecule chains) is the misunderstanding here.

P.S. for the chemists out there, please excuse my laymans description/understanding of the oxidation process.

 

[michaeld16]

Not as easy. You can't just get your hand in there to give them a wipe.

I like to avoid any physical wiping of plastic just wiping your hands along plastic will scratch it, hot pbw will remove most krausen gunk in little time, or just cold napisan as I use most of the time will remove the crud in a day or to.

 

[Kev R]

If you are using bleach you should not be rinsing with starsan. Rinse the bleach with lots of water then use starsan. Starsan is an acid and bleach is a chlorine think it makes chlorine gas, used to kill troops in ww1. May also leave some in your brew (chlorine not troops)

 

[Seeker]

I don't rinse with star San, just use it directly prior to use after rinsing with water.

@Jack of all beers.
That makes sense, and would explain the difficulty in tying it down. It doesn't taste like stale beer really, and is a metallic kind of taste. Like sucking water out of wet cardboard full of rusty staples.

 

[tugger]

If your concerned about oxygen in your beer you could send me 2 bottles and I can run it through the oxygen meter. Gives results in parts per billion.

 

[Jack of all biers]

@Jack of all beers.
That makes sense, and would explain the difficulty in tying it down. It doesn't taste like stale beer really, and is a metallic kind of taste. Like sucking water out of wet cardboard full of rusty staples.

Metallic and cardboard? Well I'll take your word at the rusty staples bit. My suggestion is to read, read, read and read some more. Research, practice and research some more.

Have a good look at the attached beer faults guide and use the word search function for metallic and cardboard (or other descriptions you can come up with) . You may find a few things you could change or improve. I got it from someone previously posting on this forum (thanks to who ever that was).

EDIT - a quick word search on "rusty" brings one to Metallic which amongst other causes states 'Metallic notes might also arise due to products of lipid oxidation, through processes which aren't fully understood.'
I have to admire who ever wrote it as I would never have thought it possible.

View attachment Complete_Beer_Fault_Guide.pdf

 

[mxd]

Do u add air or o2 to the cube when fermenting in the cube ? Do u have the issue if u ferment not in the no chill cube ?

 

[Seeker]

I always add air, and the one that was ok was done in the no chill cube.

 

[barls]

id try replacing the bleach with sodium per carbonate aka nappy san

 

[indica86]

Read again. From Palmers 'online book' under the chapter 7 'Boiling and cooling'

'7.4 Cooling the Wort

At the end of the boil, it is important to cool the wort quickly. '

Thats is just plainly WRONG.

 

[Jack of all biers]

Thats is just plainly WRONG.

I'm wrong that it's not in Palmers online book? Pretty sure my copy and paste function is working correctly. Maybe I should get in the computer guy to check it.......

Wait, you're arguing that Palmer is wrong in what he's written. As I was quoting Palmer to point out that he did infact talk about oxidation dangers in hot wort (which is one of the reasons he states it is important to cool the wort quickly) I think you can forgive me for only quoting a couple of sentences and not the whole book.

Stating that one sentence in a chapter is wrong without taking into context a whole chapter or paragraph and then not backing it up with a reason or even bothering to research the chapter quoted is a little silly.

I'd suggest you write Palmer a letter telling him he's wrong. Or maybe write your own book, have a brewing radio show, be famous in the home brew world for having a good idea about the subject....

Edit - Next time you quote something don't cut out the bit that won't suite your purposes.

Read again. From Palmers 'online book' under the chapter 7 'Boiling and cooling'

'7.4 Cooling the Wort

At the end of the boil, it is important to cool the wort quickly. While it is still hot, (above 140°F) bacteria and wild yeasts are inhibited. But it is very susceptible to oxidation damage as it cools.'

And in the next paragraph;

'Minimize splashing to avoid oxidation.'

 

[manticle]

He's just talking about the statement 'wort MUST be chilled quickly' - something no-chillers ignore all the time without massive perceived ill effects.

At least that's my interpretation.

 

[Jack of all biers]

manticle, I get that is were he's coming from, but blanket statements that something is plainly wrong just because one sentence quoted doesn't suite the belief in one method? Given this thread is about oxidation problems using a no chill process I think we all get that it's not always important to cool the wort immediately.

The crux of the quote is that someone mis-read (or mis-remembered) Palmer's book. I was correcting that mis-read and at the same time making a point to the OP of the risks of oxidation because of exposure to air (especially because of splashing). If we wanted to, we could take a singular sentence from any manual or book on a subject and correctly state that it is wrong, but without the context then we are in danger of fooling others who are not familar.

Edit - To avoid misrepresentations or mis reads there is more to be read in Palmers book on aeration and oxidation that applies to no chill methods also. It can be found in the chapter;

6.9.3 Aeration is Good, Oxidation is Bad