# Hot Side Aeration



## Stuster (16/1/06)

Just spotted what I thought was an interesting topic on brewboard on hot side aeration. I've been careful to avoid it, but maybe there's no real reason to be paranoid about it.

Anybody done anything similar? Any strong views for or against? :unsure:


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## AndrewQLD (16/1/06)

I can't say I have ever experienced oxidation from HSA, although I don't make a habit of throwing my hot wort around either, but there is always a bit of splashing and it hasn't affected my beers so far that I can tell. So my belief is that it is a bit of a fallacy and just one more thing to cause budding new brewers to shy away from the hobby. However oxidation after fermentation is a different story.

Cheers
Andrew


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## Ross (16/1/06)

I honestly believe that HSA in the homebrewing set-up is something not to be concerned about... I don't go out of my way to splash hot wort about, but I've never experienced it & to my knowledge not met anyone else who has either...

I guess it's a concern on a commercial scale though, where a bad batch could ruin your financially...


cheers Ross...


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## Darren (16/1/06)

Oxidation is really only a problem with longer term storage of beer. Most home brewers use soooo much hops that it masks the flavours of oxidation.
If you are thinking of making a lightly hopped (<30) IBU lager I would avoid any HSA as it will shine through.
cheers
Darren


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## Ross (16/1/06)

Darren said:


> Oxidation is really only a problem with longer term storage of beer. Most home brewers use soooo much hops that it masks the flavours of oxidation.
> If you are thinking of making a lightly hopped (<30) IBU lager I would avoid any HSA as it will shine through.
> cheers
> Darren
> [post="102849"][/post]​



Is this from actual experience Darren?


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## Darren (16/1/06)

Oxidation in light beers Ross? Yes, I presume you have never judged any light beers.

cheers
D


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## Gulf Brewery (16/1/06)

Stuster

Oxidation can occur on the hot side (mash / boil) and cold side (fermentation / bottling / kegging)

It does take time for it to be noticed in a beer as the oxidation of a beer doesn't happen overnight. You may find that a bottle beer that has been stored badly (ie excessive heat) might show oxidation more than a bottle of beer that has been stored correctly and will be more likely to show any other flavours from any infections as well. 


You rarely notice it if you keg your beers as most kegs don't last that long compared to bottle beers (well, not around here anyhow)

Cheers
Pedro


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## Mr Bond (16/1/06)

I experienced it once many years ago in a pale ale type brew of about 25 ish IBU's.

In the early more care free days.  
Extract only for hour boil ,and tipped(with much splashing) 2 mins after boil into fermenter and topped up with cool water.No racking to primary so oxidation could only have been from HSA(dodgy practices).
Not evident Up to 6 months,but a surprise find of 1 bottle @ 9 months had it there no doubt  . One and only time I've ever had it though.

Nowadays I'm much more educated/careful about these things.


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## Ross (16/1/06)

Darren said:


> Oxidation in light beers Ross? Yes, I presume you have never judged any light beers.
> 
> cheers
> D
> [post="102856"][/post]​



That wasn't the question Darren, but then why am I not surprised  - Judging someone elses beer & finding oxidisation is no proof of HSA. I've tasted many beers suffering from oxidisation, many of them kit beers where HSA is highly unlikey to be the cause. 

Cheers Ross...


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## Darren (16/1/06)

Never had a kit with it. Coldside airation is actually essential (usually) for carbonation. The oxygen is quickly used by the yeast.
Had lots of counter-pressure filled beers with it though 8)


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## big d (16/1/06)

hot side airation  blah blah never tasted it or come across it.
what does it taste like?????? oxidation i hear you say...
so describe to me what oxidation tastes like to a person who believes he doesnt know what oxidation tastes like. <_< 

cheers
big d


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## AndrewQLD (16/1/06)

big d said:


> hot side airation  blah blah never tasted it or come across it.
> what does it taste like?????? oxidation i hear you say...
> so describe to me what oxidation tastes like to a person who believes he doesnt know what oxidation tastes like. <_<
> 
> ...



Yeah BigD, your right an overated geeky term. Oh, this beer is oxidised!!!

Cheers
Andrew


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## Ross (16/1/06)

Darren said:


> Never had a kit with it. Coldside airation is actually essential (usually) for carbonation. The oxygen is quickly used by the yeast.
> Had lots of counter-pressure filled beers with it though 8)
> [post="102872"][/post]​



you'd make a great politician Darren  

Have you had a beer that you know was oxidised from HSA? 
I don't think CSA or counter-pressure beer has anything to do with the original or subsequent questions  

cheers Ross


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## Darren (16/1/06)

No, never had one I knew was oxidised by HSA. That would not be blind tasting. Certainly tasted alot of CARDBOARD in crystal clear beers with no yeast sediment in the bottle though.
Hope that answers both your questions?

cheers
Darren


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## Ross (16/1/06)

Darren said:


> No, never had one I knew was oxidised by HSA. That would not be blind tasting. Certainly tasted alot of CARDBOARD in crystal clear beers with no yeast sediment in the bottle though.
> Hope that answers both your questions?
> 
> cheers
> ...



Yes thankyou  

Cheers Ross


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## Gulf Brewery (16/1/06)

big d said:


> so describe to me what oxidation tastes like to a person who believes he doesnt know what oxidation tastes like. <_<
> 
> cheers
> big d
> [post="102875"][/post]​



OK bigd, I will bite 

I judged with a person that could smell oxidation, I can't smell it but I can taste it. To me it is a stale wet cardboard flavour and it is often combined with other defects (see my earlier post) 

Cheers
Pedro


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## big d (16/1/06)

thanx darren.the dictionary i looked up basically refered to rust.
as for cardboard taste cant say ive chewed on cardboard so will give it ago sometime h34r: to see what it tastes like.

cheers
big d


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## AndrewQLD (16/1/06)

Darren said:


> No, never had one I knew was oxidised by HSA. That would not be blind tasting. Certainly tasted alot of CARDBOARD in crystal clear beers with no yeast sediment in the bottle though.
> Hope that answers both your questions?
> 
> cheers
> ...



Isn't that a description of light struck beers???


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## Gulf Brewery (16/1/06)

AndrewQLD said:


> Isn't that a description of light struck beers???
> [post="102890"][/post]​



Light struck is more what is desribed as "skunky" and you can smell that easily. 

bigd - do you me to send you some cardboard?

Pedro


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## Darren (16/1/06)

AndrewQLD said:


> Isn't that a description of light struck beers???
> [post="102890"][/post]​




Andrew,
That would be a mercaptan type smell. Bit like B-mercaptoethanols which I seem to be particulaly sensitive to. I have heard of it associated to a skunk smell. Never smelled a skunk so dunno.

cheers
Darren


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## AndrewQLD (16/1/06)

Skunky newspapers, yak. Glad to that I haven't smelt it.

Cheers
Andrew


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## mika (16/1/06)

Hmmm, I'm a K+K man (not the white sheets h34r: ) and I always mix the wort in with hot water to make sure it's in the mix and not in a clump on the bottom of the fermenter, is this a bad thing ?
Haven't had a brew that tasted like wet carboard (necessary evil if you're lacking a bit of fibre in your diet) or skunk (presume this to be akin to sweaty gym socks).

Ross and Darren, where's the ring going to be setup, I'll buy tickets :blink:


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## vlbaby (16/1/06)

Ross said:


> That wasn't the question Darren, but then why am I not surprised  - Judging someone elses beer & finding oxidisation is no proof of HSA. I've tasted many beers suffering from oxidisation, many of them kit beers where HSA is highly unlikey to be the cause.
> 
> Cheers Ross...
> [post="102868"][/post]​



Ross , of the beers that you tasted that indicated signs of oxidisation, were any undrinkable because of it? or was the flavour one that only a discerning palate would detect? 
just curious to know.

vlbaby.


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## Darren (16/1/06)

AndrewQLD said:


> Skunky newspapers, yak. Glad to that I haven't smelt it.
> 
> Cheers
> Andrew
> [post="102894"][/post]​




Andrew,
It isn't a prominent flavour that is obvious. Some people (those looking for it) can taste it.
Its a flaw in a light lager. Thats it.

cheers
Darren


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## big d (16/1/06)

hi pedro
if you enclose 1/2 dozen of gulfs finest inside some cardboard then yep you can send some up my way.  
nothing like washing down the cardboard with fine handcrafted adelaide beers.

cheers
big d

unashamed plug for gulf brewery beers of which i havent sampled yet.


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## Ross (16/1/06)

vlbaby said:


> Ross said:
> 
> 
> > That wasn't the question Darren, but then why am I not surprised  - Judging someone elses beer & finding oxidisation is no proof of HSA. I've tasted many beers suffering from oxidisation, many of them kit beers where HSA is highly unlikey to be the cause.
> ...



vlbaby,

In my experience it's usually been a mix of several problems, making the beer pretty undrinkable... I've tasted cardbord flavours on there own, but one particular beer, i know was made with stale brown hops & this was probably more the cause than oxidisation... 
but yes, I've tasted drinkable ones - but on the whole, not finished the glass...

cheers Ross


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## Darren (16/1/06)

Big D,
Once you try Gulf beers all yours will fail into comparison and you will never drink your own again and think yours are good.
be warned


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## Aaron (16/1/06)

Well I have had a beer become obviously oxodized due to HSA. It was my second AG and didn't realise I shouldn't be doing it. It took a while to present it's self, early in it's life it picked up a third at a comp. However, Brad and Kai can attest to the fact that the cardboard and what I would call sweet sherry like flavours were there as I had them both taste it at Grumpy's one day.


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## berapnopod (17/1/06)

Oxidation is usually referred to as smelling like wet cardboard, but I have never got this smell, except when smelling the chemical responsible on its own. To me oxidation in beer happens like this:

First of all the hop flavour and aroma is muted and then virtually disappears.

Then apparently its the wet cardboard stage.

Following that, the aroma is more like over-ripe pineapples. This is what I look for in oxidised beers and I can spot it, but this is quite an advanced stage.

Finally, the aroma and flavour is something more like sherry, which is pretty easy to pick.

---------------------------

On the subject of lightstruck beers...
Yep, the term "skunked" is used because the Americans have lots of skunks, and they stink. They stink with a very distinctive stink, and its the same stink in a lightstruck beer. I believe the Pommies call it "Catty".

In any case, if you were ever gullible enough to think that theres no such thing as lightstruck beer, then buy two bottles of beer. They have to be in clear bottles (eg Corona), or maybe green bottles (Heineken). Put one in the fridge and the other on the window sill - in full sunlight - for an hour or so. Then put the window sill bottle in the fridge and let both cool to a pleasant temperature.

Open the one thats been in the fridge. Smell it. Sip it. Think about it.
Then open the one that was on the window sill. See if you can tell the difference.

Go on. Try it!  

Berp.


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## sosman (17/1/06)

berapnopod said:


> lightstruck beer, then buy two bottles of beer. They have to be in clear bottles (eg Corona), or maybe green bottles (Heineken). Put one in the fridge and the other on the window sill - in full sunlight - for an hour or so. Then put the window sill bottle in the fridge and let both cool to a pleasant temperature.
> [post="102946"][/post]​



Half the heinekens (all 2 of them) I have tasted are already light struck. Also some beers are impervious to this, something to do with the formulation of the hops (or lack of hops). Homebrew is excellent for this experiment, half an hour in the sun and you will notice the difference as soon as you open the cap.

Interestingly, I noticed a very distinct lightstruck smell in a VB that someone had left sitting in a glass for an hour or so under flourescent light.


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## Batz (17/1/06)

Is this not what we called 'rewy' beer years ago

I remember my old man saying this beers gone 'rewy'
Talking light struck here

HSA , has never given me a problem that I know of.

Batz


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## Gough (17/1/06)

I've not knowingly had a problem with HSA either, but like most brewers I've come across I don't splash hot wort around if I can help it... That said I can most definitely taste and smell oxidised beers - for me the sherry like description hits the mark. 

Light struck beers are the pits. Why do bottlos seem to go out of their way with imported beers in clear/green bottles in particular to stick them as close to a fluoro light as possible. We have a fantastic bottlo here in Newcastle that is run by a real 'enthusiast' and who consistently stocks new and interesting beers from around the world as soon as he can get his hands on them. He has almost put himself out of business doing so, but is a 'true believer'. For all that he STILL unpacks the cartons and sticks them on shelves with fluoros running along the top almost touching the bottles... I asked him about it one day and suggested he just keep one on display and the rest out of the light and he just didn't get it and reckoned no-one else had complained...

Shawn.


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## Ross (17/1/06)

berapnopod said:


> Buy two bottles of beer. They have to be in clear bottles (eg Corona), or maybe green bottles (Heineken). Put one in the fridge and the other on the window sill - in full sunlight - for an hour or so. Then put the window sill bottle in the fridge and let both cool to a pleasant temperature.
> 
> Open the one thats been in the fridge. Smell it. Sip it. Think about it.
> Then open the one that was on the window sill. See if you can tell the difference.
> ...



I'm sure I must have drunk a light struck beer in my time, but can't honestly say I've ever recognised it as such... Time to do the taste test...


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## Darren (17/1/06)

In my experience Corona is almost always light-struck. Not sure buying two and putting one on the window sill will be a good test. Ross, when you open the bottle immediately sniff the top of the bottle. You should get a good whif of it then.
cheers
Darren


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## Ross (17/1/06)

Darren said:


> In my experience Corona is almost always light-struck. Not sure buying two and putting one on the window sill will be a good test. Ross, when you open the bottle immediately sniff the top of the bottle. You should get a good whif of it then.
> cheers
> Darren
> [post="102967"][/post]​



I intend to use homebrew - will pour test into a clear bottle - planning on using a light english bitter so as not to have hop aroma masking the effect.

cheers Ross


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## berapnopod (17/1/06)

Darren said:


> In my experience Corona is almost always light-struck. Not sure buying two and putting one on the window sill will be a good test. Ross, when you open the bottle immediately sniff the top of the bottle. You should get a good whif of it then.
> cheers
> Darren
> [post="102967"][/post]​



I agree that most coronas, heinekens etc are probably lightstruck to some extent. My point was that you'll easily be able to tell the difference between a little lightstruck and a lot. I once did the test with a bunch of others and we could all smell the lightstruck one within five seconds of the bottle opening.

Berp.


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## warrenlw63 (17/1/06)

Lightstrike hits quickly.

I've drank a few of my own under the pergola at home and have detected it in as little as 5-10 mins in moderate levels.

Oddly enough. A small amount of it never worries me. h34r: In fact I've had a bottle of La Chouffe with some mild light strike and thought that it actually enhanced the flavour a little bit. B) 

Warren -


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## Bobby (17/1/06)

> I guess it's a concern on a commercial scale though, where a bad batch could ruin you financially...



unless you are CUB and brewing Carlton Cold...


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## bindi (21/1/09)

Old subject I know, But.

If it's going to happen it will be with this stuff up. :angry: 

Just filled a cube with boiling wort when the tap [only cube with one] started to leak then spat itself out, lost a couple of liters before I had another cube under it , lucky I had thick rubber gloves on and a cube close by, anyway, it was froth and bubble into the next cube and hot wort everywhere.
HSA myth or fact?
The Gods are telling me something [and it's NOT to no chill so lay off that] it being my first Reinheitsgebot beer for awhile. :lol:


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## Polar Beer (21/1/09)

bindi said:


> Just filled a cube with boiling wort when the tap [only cube with one] started to leak then spat itself out, lost a couple of liters before I had another cube under it , lucky I had thick rubber gloves on and a cube close by, anyway, it was froth and bubble into the next cube and hot wort everywhere.



Bindi. I have no HSA advice what so ever. But I did have bloody good laugh :icon_cheers: 
You should frame those gloves.


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## Airgead (21/1/09)

At the risk of opening up and old (and very smelly) can of worms, I have a pet theory about HSA. From what I have observed, it seems to be much more of a concern among brewers with fancy recirculating systems. The US podcasts seem to make a big noise about it but over there every man and his dog seems to have a recirculating system. I know the craftbrewer radio guys from Townsville add metabisulphate to the mash as they are so paranoid about HSA but they also use recirculating systems.

My theory says that HSA exists and is caused by excessive aeration in the pumps (either through cavitation or air leaks). It is an issue in recirculating systems because the pump is running pretty much all the time. Those of us who use gravity or just use a pump for a short while sparging or draining the kettle seem to be unaffected.

The other explanation is that recirculating systems make such good beer that HSA becomes noticeable. But I like my first theory best.

I'll stick to using my nice, simple 3 tier gravity system and give HSA a miss...

Cheers
Dave


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## katzke (21/1/09)

Well HSA is a real problem. That said it is not a problem for home brewers. It is only a problem for commercial brewers that can not control how their beer is transported and stored. HSA is caused by enzyme action and as I recall the enzyme is denatured at 140F. 

The basics are the only way to avoid HSA is to remove the O2 from the grains and the water before you mash. I will look and see if I can find a post I made on the subject.


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## matti (22/1/09)

Hers is little about HSA from one of my favorite places where all the information is not debated but factual findings.
Linky


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## katzke (22/1/09)

katzke said:


> Well HSA is a real problem. That said it is not a problem for home brewers. It is only a problem for commercial brewers that can not control how their beer is transported and stored. HSA is caused by enzyme action and as I recall the enzyme is denatured at 140F.
> 
> The basics are the only way to avoid HSA is to remove the O2 from the grains and the water before you mash. I will look and see if I can find a post I made on the subject.



The major reaction that causes HSA is the enzyme lipoxygenase that binds O2 to lipids and melanoidins. This happens in the mash at 100 to 130 degrees. The lipoxygenase enzyme is denatured above that temperature. Denatured is basically killed so it can not have any effect after that point. The water and the grains have O2 in them unless it is removed some way. Campden tablets, cinnamon, and coriander added to the mash are reported to work as anti-oxidants. After time the O2 is released as part of the normal breakdown of the beer (staling).

In my research on the subject oxidization is very complicated and other reactions may cause oxidized wort. The common belief is there are way more important proven brewing practices that will effect the taste of home brewed beer. Post ferment oxidization will show up faster then the effects of HSA will.


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## matti (22/1/09)

Ive got to agree there katzke.

A though after reading old farts attempt to cause hotside aeration on his Rye beer on the brew board.
If you brerwing process is adequate then there be little the Oxygen can attach it self to and that confirming that even when brewing lager beer decoction /step mashing will decrease the chances of oxidisation.
And since darker beer have all the melanoidan needed to protect the beer from HSA the chance are very slim for the home brewer to spoil the beer prior boiling the wort. Most beers are consumed within 3 month time any way.


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## Goose (23/1/09)

This was posted by Tangent a couple of years back, when I asked the same question. Answered alot of them for me. 




http://media.libsyn.com/media/basicbrewing/bbr11-02-06.mp3


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## reviled (23/1/09)

I brewed a Munich Dunkel at a mates and didnt have a syphon handy, so to get it into a cube, poured my wort into my mates HLT from my kettle, it splashed about enough to foam up and get aerated, and then from the HLT I dumped it from the tap into the cube, again, it splashed and there was more foam, I was paranoid as hell, but I tasted the fruits of my labour the other day, no wet cardboard taste, no oxidisation, just a really nice tasty beer B)


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## Kai (23/1/09)

If there's not much of a time span between brewing and drinking you wouldn't notice any oxidation anyway. Try again in a few months as the real test to give any oxidation reactions time to really develop.


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## reviled (23/1/09)

Kai said:


> If there's not much of a time span between brewing and drinking you wouldn't notice any oxidation anyway. Try again in a few months as the real test to give any oxidation reactions time to really develop.



Its a lager, so I brewed it about 8 weeks ago... 

And ive also had a "wet cardboard" taste in a beer that went from brew to mouth in 10 days which I was told was hot side aeration, but I fail to see how I got it in that brew as there was no splashing or anything like that


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## muckanic (23/1/09)

Back when I participated on HBD, this topic invariably got derailed by a fundamental difference between the pros and the amateurs, namely, artificial vs natural conditioning. A beer with live yeast (or at least live enzymes) has a natural reductive power that packaged beer does not. For this reason, I would question the wisdom that oxidation is less prevalent in kegs than bottles, and even that old beer is more prone than young beer. All the cardboard flavours I have ever experienced from crappy oxidised liquid extract or crappy brown hop pellets were there from the word go - they didn't need time to develop. I must admit that I have never abused my wort sufficiently to simulate cheap liquid extract, which I suppose would be an interesting experiment. The colour would presumably be a pretty strong indicator. And there's another aspect that the HSA freaks always neglect to mention - they're making filtered and/or pasteurised bloody lager! Bottle conditioning is certainly reductive enough to correct any acetaldehyde that may have developed as a result of open ferments going on too long. I have had sherry notes develop in prolonged secondaries in permeable fermenters, but that was usually deliberate and is a different kettle of fish from the cardboard staling syndrome anyway. Lastly, I suppose if you left the brew on enough sludge then there would be some possibility of lipid rancidity, but in that case it would probably be a deliberate act once again.


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