Is Hot Side Aeration A Big Worry?

[bradsbrew]

Cheers Guys. Often wondered what the fear was about. As stated not something to get anal about but be aware of.

Brad

 

[flattop]

If it gets worse with age, my beer is at no risk...

 

[Thirsty Boy]

It binds oxygen to the wort, which then travels through to the final beer (in the keg or bottle). This promotes oxidation and quicker staling of the beer, from memory sherry and cardboard flavours.

One of the main reasons to be a little careful - is that by allowing oxidation to occur in your hot wort, you are using up antioxidants that would survive through to your packaged beer and help to protect it against the far great issue of post fermentation oxygen

Most (not all) of the products of HSA are volatile and evaporate during your boil - but each quantum of antioxidant that is used up during your "hot" phase .. is one less for later

 

[Screwtop]

its only a worry if you have your head up your arse...

Shite! never knew that :lol:

I use a pinch of Sodium Metabisulfite in the mash as recommended. Some use camden tablets (same thing) in their brewing water to remove chlorine/chloramides and reduce oxidation risk.

Screwy

 

[Stuster]

Theres a Brewstrong episode that goes into a bit of detail about it
http://www.thebrewingnetwork.com/shows/Brew-Strong
Lots of good info there

Definitely a good thing to listen to if you're interested in HSA. They talked to a leading brewing scientist, Charlie Bamforth, who was really knowledgeable and very down to earth. His advice was that HSA was not a myth but as long as you took simple precautions to avoid it, it wasn't a major issue (even at the large brewery size). It was much more important to keep your beer cold after fermentation to prevent staling.

 

[technocat]

So how exactly does HSA effect your beer?? Ive heard all the watch out for splashing or dont just pour it into ya vessel you'll get HSA but what does it do???. Sorry if this has already been answered but............

HSA is a phenomenon produced by introducing air/oxygen into hot wort. It manifests itself as a wet papery/cardboard like aftertaste on the back of the palate when drinking the beer. It is neither detected in aroma nor the first taste on the tongue and ruins an otherwise good brew. Dry hopping diminishes the unpleasant taste slightly but if you have it you are stuck with it. I speak from experience as HSA which at the time I had no idea of, plagued my early brews until some timely advice from a very experienced brewer how to redesign my setup finally eradicated the problem.

Cheers

 

[Stuster]

Interesting, beernut. What were you doing that was causing it? And how long after fermentation did it show up?

 

[katzke]

HSA is a phenomenon produced by introducing air/oxygen into hot wort. It manifests itself as a wet papery/cardboard like aftertaste on the back of the palate when drinking the beer. It is neither detected in aroma nor the first taste on the tongue and ruins an otherwise good brew. Dry hopping diminishes the unpleasant taste slightly but if you have it you are stuck with it. I speak from experience as HSA which at the time I had no idea of, plagued my early brews until some timely advice from a very experienced brewer how to redesign my setup finally eradicated the problem.

Cheers

Are you confusing HSA with post ferment oxidization? I have never seen any qualified reference to HSA giving the wet cardboard/sherry like taste to beer. I have only read reference to the potential of accelerated staling. Post ferment oxidization will give that wet cardboard taste to beer. If you know of one please let me know.

 

[RobboMC]

I have only read reference to the potential of accelerated staling. Post ferment oxidization will give that wet cardboard taste to beer. If you know of one please let me know.

One word - Palmer

This excellent book clearly states HSA leads to a wet/cardboard sheery aftertaste. Seems the HSA oxygen is tied up in the beer
throughout fermentation, gets bottled; and then gradually gets released back into the gas space in the bottle over time. I can see how
this could lead to the same resulting off-flavour as post-fermentation oxygen, but of course has a different cause.

Oxygen introduced by cold aeration before fermenting apparently gets eaten up by the yeasties before the sugars, but the HSA oxygen is tied up at that point so it doesn't get consumed.

Someone should invent a yeast that eats any hot oxygen.

 

[katzke]

One word - Palmer

This excellent book clearly states HSA leads to a wet/cardboard sheery aftertaste. Seems the HSA oxygen is tied up in the beer
throughout fermentation, gets bottled; and then gradually gets released back into the gas space in the bottle over time. I can see how
this could lead to the same resulting off-flavour as post-fermentation oxygen, but of course has a different cause.

Oxygen introduced by cold aeration before fermenting apparently gets eaten up by the yeasties before the sugars, but the HSA oxygen is tied up at that point so it doesn't get consumed.

Someone should invent a yeast that eats any hot oxygen.

Well not to get a riot going but Palmer is all wet on the subject of HSA and even admits it in at least one interview. It also depends on what version of his book you are referring too as he has made several revisions. The last I heard he was blaming an enzyme for HSA and that has been shown to have little influence on the staling effect of time on beer.

So while Palmer may know much more then I do about brewing I do not consider his book authoritative as it has many errors in it, especially the on-line first version.

Brewing beer is a very complicated chemical/biological reaction and no one fully understands it. We have some basic guidelines to follow and they are not based on science but on historical observations. Some of those observations have been shown to have scientific merit but not totally understood.

Give the above referenced interview a listen and you will hear from an expert how much is understood about brewing.

 

[technocat]

Interesting, beernut. What were you doing that was causing it? And how long after fermentation did it show up?

No I am talking prefermetation. I reduced tubing size down to 3/8 that included hosetails and ball cocks full open not partially. Sparge ring on top of grain bed and no air leaks between mash tun and kettle. I keg and don't bottle so off taste is immediate after kegging. Definitely no oxidization in fermenter and when I keg I use a closed system from fermenter tap, to dip tube post. Result no more off tastes as described in my previous post.

Cheers

 

[jonocarroll]

Brewing beer is a very complicated chemical/biological reaction and no one fully understands it.

Have a thumb through the 888 pages or so of 'Brewing: Science and Practice' textbook sometime and then say that no-one fully understands it. You honestly need a few years of university chemistry before you can even understand half the words. :huh:

 

[Stuster]

Have a thumb through the 888 pages or so of 'Brewing: Science and Practice' textbook sometime and then say that no-one fully understands it. You honestly need a few years of university chemistry before you can even understand half the words. :huh:

Have a listen to the interview linked to above before saying that people do fully understand it.

 

[chalky]

This is a topic I am reading up on at the moment. The pro's often actively design wort spreading in the brew kettle to speed up the evaporation of volatiles. Refer to the 2 photos from journal articles below.

Is anybody able to link me to a journal article / respected text book / or even a professional brewer who can tell me that HSA is something to worry about?

Seems that Palmer in How To Brew is the only person to publish that HSA will result in cardboard or sherry like flavours in the resultant beer.

Technical Summary - The Process of Wort Boiling. Pages 26-28
The Brewer International Journal
www.igb.org.uk
June 2002

Wort Production Article. Pages 249-254
MBAA TQ Journal
Master Brewers Association of the Americas
Volume 40. Number 4. 2003

 

[Feldon]

From BrewingTechniques magazine, November/December 1993

"Wort contains melanoidins and tannins that are readily oxidized at high temperatures. If air is introduced during wort production--in other words, on the hot side --these substances will be oxidized and later, in the finished beer, they can turn around and give up their oxygen to alcohols that were created during fermentation. An oxidized alcohol is an aldehyde, and aldehydes are the bad guys that are responsible for all the stale, old-beer flavors we have all encountered in far too many imported brews ...

"Brewpubs and home brewers don't have nearly as much to be concerned about as shipping breweries because they keep their beer close to home rather than sending them out into the cruel world where they can suffer all kinds of insults. Storage temperature has a lot to do with how fast beer oxidizes. So does agitation. There really is something to the old saying that beer doesn't travel well. Getting knocked around in the back of a truck does take a toll on packaged beer, and temperature is an even bigger factor. But even at low temperatures, kept absolutely still, beer will oxidize eventually. That is why the best plan is to store it cold and drink it quick."​

Sourced from: http://www.brewingtechniques.com/library/b...r.html#aeration

 

[mje1980]

NO

 

[chalky]

I have read the journal article and found the following sentences of interest.

The insidious thing about hot-side aeration is that it can cause staling even in a beer that has been carefully handled during fermentation and subsequent stages. A freshly bottled beer may have a dissolved oxygen content of almost nothing and yet oxidise in a matter of weeks if the hot wort was mishandled.

The question is, is this theory or opinion or is this conclusion based on some scientific evidence/experiment?

From BrewingTechniques magazine, November/December 1993

"Wort contains melanoidins and tannins that are readily oxidized at high temperatures. If air is introduced during wort production--in other words, on the hot side --these substances will be oxidized and later, in the finished beer, they can turn around and give up their oxygen to alcohols that were created during fermentation. An oxidized alcohol is an aldehyde, and aldehydes are the bad guys that are responsible for all the stale, old-beer flavors we have all encountered in far too many imported brews ...

"Brewpubs and home brewers don't have nearly as much to be concerned about as shipping breweries because they keep their beer close to home rather than sending them out into the cruel world where they can suffer all kinds of insults. Storage temperature has a lot to do with how fast beer oxidizes. So does agitation. There really is something to the old saying that beer doesn't travel well. Getting knocked around in the back of a truck does take a toll on packaged beer, and temperature is an even bigger factor. But even at low temperatures, kept absolutely still, beer will oxidize eventually. That is why the best plan is to store it cold and drink it quick."​

Sourced from: http://www.brewingtechniques.com/library/b...r.html#aeration

 

[Nick JD]

I can't seem to find it, but I saw this photo of a big commercial brewery's transfer of hot wort from one place to another and it was gushing out of a pipe and splashing everywhere.

 

[Maheel]

i got NFI really

but something that has always worried me is, I worry heaps about getting it cooled via no chill with no splashing / oxygenating of the wort into the cube

and then the next day when cooled, splash it all over the place to aerate it for the yeast ?
some even put air stones in etc ?

it seems to be crazy

 

[Bribie G]

Didn't seem to worry the old school guys, but then they didn't send their brews half way around the planet to Dans.

coolships:





And apparently Pilsner Urquell used coolships until fairly modern times.