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General Category => General Homebrew Discussion => Topic started by: Hersey on September 28, 2018, 04:16:42 pm

Title: Oxidization
Post by: Hersey on September 28, 2018, 04:16:42 pm
Is it only transfering from the fermenter to bottles and/or kegs that negative aspects of oxidization occur?  I've often wondered about transfering into a brew kettle when doing all grain directly from the mashtun?  Aerating the wort before, during or immediately after pitching the yeast is acceptable.
Title: Re: Oxidization
Post by: narcout on September 28, 2018, 04:44:32 pm
Unless you're following the full low oxygen brewing protocol (including deoxygenating all of your strike water, etc.), it's pretty unlikely you're going to notice any ill effects from small scale, additional oxygenation on the hot side.

That said, how are you transferring wort from the mashtun to the kettle?  It's good practice to minimize splashing, etc. 
Title: Re: Oxidization
Post by: Hersey on September 28, 2018, 06:12:53 pm
I last dumped from a pot into the bk... but it's a stout so not Too worried.  Just setting up my equipment again now, putting it in the carport... last 3 batches were under open skies and everything had to be handled manually.  Hmmph... started out just showing my son in law how to brew, gave him John Palmer's book ... now I've got the bug again!  Lol!
Title: Re: Oxidization
Post by: KellerBrauer on September 29, 2018, 06:17:11 am
I agree with narcout.  However, I also must say that many brewers I’ve spoken with put way too much emphasis of the elimination of oxygen in the “pre-aeration” stage of the brewing process.  I don’t believe that’s necessary at all.  I believe it’s far more important to put greater emphasis on minimizing oxygen post fermentation.
Title: Re: Oxidization
Post by: denny on September 29, 2018, 08:50:43 am
Unless you're following the full low oxygen brewing protocol (including deoxygenating all of your strike water, etc.), it's pretty unlikely you're going to notice any ill effects from small scale, additional oxygenation on the hot side.

That said, how are you transferring wort from the mashtun to the kettle?  It's good practice to minimize splashing, etc.

I've gotta disagree with that.  Even without brewing low oxygen, there are still noticeable effects from oxygen during other processes.
Title: Re: Oxidization
Post by: majorvices on September 29, 2018, 10:45:18 am
Unless you're following the full low oxygen brewing protocol (including deoxygenating all of your strike water, etc.), it's pretty unlikely you're going to notice any ill effects from small scale, additional oxygenation on the hot side.

That said, how are you transferring wort from the mashtun to the kettle?  It's good practice to minimize splashing, etc.

I've gotta disagree with that.  Even without brewing low oxygen, there are still noticeable effects from oxygen during other processes.

totally agree
Title: Re: Oxidization
Post by: tommymorris on September 29, 2018, 11:05:22 am
Unless you're following the full low oxygen brewing protocol (including deoxygenating all of your strike water, etc.), it's pretty unlikely you're going to notice any ill effects from small scale, additional oxygenation on the hot side.

That said, how are you transferring wort from the mashtun to the kettle?  It's good practice to minimize splashing, etc.

I've gotta disagree with that.  Even without brewing low oxygen, there are still noticeable effects from oxygen during other processes.

totally agree
narcout said “it's pretty unlikely you're going to notice any ill effects from small scale, additional oxygenation on the hot side.” Emphasis on hot side.

I think that’s right. There are definitely “noticeable effects from oxygen during other processes.” But, most of those effects are from cold side oxidation if you aren’t doing low oxygen brewing (narcout’s assumption).

Title: Re: Oxidization
Post by: denny on September 29, 2018, 11:47:50 am
narcout said “it's pretty unlikely you're going to notice any ill effects from small scale, additional oxygenation on the hot side.” Emphasis on hot side.

I think that’s right. There are definitely “noticeable effects from oxygen during other processes.” But, most of those effects are from cold side oxidation if you aren’t doing low oxygen brewing (narcout’s assumption).

I've seen at least one instance that proves my point.  It is possible on the hot side whether you brew low oxygen or not.
Title: Re: Oxidization
Post by: Robert on September 29, 2018, 11:57:07 am
I don't preboil/deaerate my water or use special equipment like a mash cap, etc.  But I find that, in addition to careful, sound practice like gentle transfers and avoiding excessive stirring and splashing, using antioxidants on the hot side makes some small but noticeable difference.   Every little thing adds up, so do what you can.  But brutally rigorous cold side oxygen exclusion is a must.
Title: Re: Oxidization
Post by: narcout on September 29, 2018, 02:32:24 pm
narcout said “it's pretty unlikely you're going to notice any ill effects from small scale, additional oxygenation on the hot side.” Emphasis on hot side.

I think that’s right. There are definitely “noticeable effects from oxygen during other processes.” But, most of those effects are from cold side oxidation if you aren’t doing low oxygen brewing (narcout’s assumption).

I've seen at least one instance that proves my point.  It is possible on the hot side whether you brew low oxygen or not.

Can you please elaborate?

I did say it was good practice to avoid HSA regardless of whether one is brewing LODO.
Title: Re: Oxidization
Post by: Hersey on September 30, 2018, 06:00:33 am
Okay, well I have to admit, I suffer from CRS a lot these days.  HSA... that ring a bell!  Lol!  Well this is a stout with an SRM of about 39, but it only had an OG of 1.055, fermented(ing) with a single packet of S-04.  I added 40 Ludin's wild cherry candy drops (dissolved in hot water and chilled) to the fermenter on day six...very low activity but some has been observed.  I'm hoping it's not a total waste.  I'm working on my setup some more today.  I always enjoyed brewing so hoping I can get it together again... almost a ten year hiatus...  ::)
Title: Re: Oxidization
Post by: KellerBrauer on September 30, 2018, 06:08:31 am
It seems there is a great deal of discussion pertaining to Hot Side vs. Cold Side of the brewing process.  Instead, shouldn’t the discussion be Pre-Aeration and Post-Fermentation?  Perhaps I simply don’t understand the conversation.  But we want oxygen in the wort when we pitch.  Then, we work to avoid inclusion of oxygen after fermentation.

I want as much splashing as possible when I pump my wort from the BC through my plate cooler and into the fermenter; this can only help fermentation.

So why would oxygen on the hot side be of any concern?  Am I missing something?
Title: Re: Oxidization
Post by: ynotbrusum on September 30, 2018, 07:20:21 am
As a low Ox brewer for pale lagers, I try to avoid oxygen degradation throughout the process, but if you preboil strike water, you are pushing out O2 from the water; then if you mash in gently by underletting or slow immersion, you can limit oxygen uptake in the mashing process.  Carrying that through the boil you can reduce thermal stress with a gentle boil, then introduce oxygen after chilling the wort, but only in the presence of a healthy pitch of yeast, which will quickly eliminate the O2.

It’s not about any one thing, rather the several little things that taken together, gives a freshness that is easily missed by taking no such steps.

Just my 2cents, but I notice the difference and that is how I choose to brew those styles. YMMV.
Title: Re: Oxidization
Post by: Robert on September 30, 2018, 07:49:31 am
Everything that is present to oxidize and lead to stale beer post-fermentation is present at mashing-in.  Given that reaction rates double for every 10°C increase in temperature,  your wort can oxidize over 100x faster at mash, boil, and cooling and transfer temperatures than beer at fermentation and storage temperature.   So everything you can do to mitigate the effects of oxygen on the pre-fermentation side will produce a fresher tasting wort.  Rigorous exclusion of oxygen from the moment of pitching until the beer hits the glass will preserve flavor as long as possible; it's a question of what initial product you're preserving.   Hence the low-oxygen brewhouse technology implemented by the Germans in the last 50 years to extend shelf life of their fragile export Pilsners, which are nonetheless skunked to undrinkability even before their green bottles leave the filling line....  Many measures are being taken by homebrewers, including use of antioxidants and adsorbants forbidden by German custom,  and their effects have experimentally been shown to be even more significant at the homebrew level, probably because of relative surface area exposure and other scale effects.  Again, it's not all or nothing, or any one thing, it's cumulative effect.  And +1 on reducing thermal stress, that may be the best bang for the buck.
Title: Re: Oxidization
Post by: Hersey on September 30, 2018, 08:00:28 am
Interesting,  I thought a more rigorous boil was desired.  I'll have to turn my burner down and give it a try.
Title: Re: Oxidization
Post by: denny on September 30, 2018, 08:36:36 am
narcout said “it's pretty unlikely you're going to notice any ill effects from small scale, additional oxygenation on the hot side.” Emphasis on hot side.

I think that’s right. There are definitely “noticeable effects from oxygen during other processes.” But, most of those effects are from cold side oxidation if you aren’t doing low oxygen brewing (narcout’s assumption).

I've seen at least one instance that proves my point.  It is possible on the hot side whether you brew low oxygen or not.

Can you please elaborate?

I did say it was good practice to avoid HSA regardless of whether one is brewing LODO.

Yes, you did, and there's no doubt of that.  I have seenm someone have trouble with large amounts of air in their runoff lineof and the beer was badly oxidized despite the rest of the processes being good.  Not conclusive, of course, but an interesting data point.
Title: Re: Oxidization
Post by: Robert on September 30, 2018, 11:14:13 am
Interesting,  I thought a more rigorous boil was desired.  I'll have to turn my burner down and give it a try.

The idea of a long, vigorous boil was to drive off DMS.  In fact, it takes at least 30 minutes on heat to convert the DMS precursor,  SMM, into DMS,  after which just a few minutes of an open boil with lots of rolling and bubbling will drive it off.  BUT.  It is very rare today to find a malt that contains the precursor, although it was common in the palest Pilsner malts decades ago, whence the old advice.  For all other purposes you can keep the lid mostly on, allowing you to reduce the heat, and just maintain a simmer providing the good rolling circulation which you need to coagulate protein and well utilize your hops. Then lid off and blast it for a bit, there are still other volatiles fo blow off. One trick I like for this is to heat the kettle asymmetrically. This will create a lot of movement and turbulence. (Here's an indicator:  if your boil off is under 10%, even as low as 6%, you're probably doing well on the thermal stress.  Above that, and especially when you hit 12%, wort will taste stale and get staler faster.) 

(I had a long brewing hiatus too, in the late 90s to early 00s, and it seemed not much had changed.  In the last 10 years, it seems everything we knew has been upended!)
Title: Re: Oxidization
Post by: mabrungard on September 30, 2018, 12:52:59 pm
It is very rare today to find a malt that contains the precursor, although it was common in the palest Pilsner malts decades ago, whence the old advice. 

Rob, I haven't found any evidence that pils malts don't have SMM in them. Maltsters have tried to find a way to malt their barley and kiln them to a low color without still having SMM. All kinds of drying and heating schemes have been tried, but the malt with successful SMM reduction had darker color.

I'm unaware that maltsters have succeeded in that quest. SMM and DMS are still a potential problem, but I do agree that the old ways of doing things weren't necessarily the best.
Title: Re: Oxidization
Post by: Robert on September 30, 2018, 01:29:51 pm
Martin, I admit it's true that the Pils malts do still have some SMM.  But what I've experienced, and what the maltsters indicate, is that they have greatly reduced it in most of their Pilsner malts.  Maybe not the very palest, less modified ones, but these are now specialty products.  Most of the Pilsner malts we encounter, and all of the other base malts, have it below the level that would justify its being a focus of attention anymore.  It would be very difficult, I think, for most homebrewers to so far reduce the intensity of their boil process that they would fail to deal with the level of SMM they will find in most any malt, including pale Pilsner.   The much greater problem is the danger of wort damage through over-boiling out of a misplaced fear of phantom DMS, it would seem -- especially when trying to make a delicate, fresh-tasting Pilsner, which is ironically when homebrewers are most often advised to boil long and hard.  As you say, DMS is a potential problem, but thermal stress is a dead certainty.   

Sure wish the audio of your seminar on boiling was available, I'd really looked forward to it.
Title: Re: Oxidization
Post by: JT on September 30, 2018, 04:19:00 pm
My current idea of "open boil." 

I brew mostly German lager styles using Weyermann malts.  (https://uploads.tapatalk-cdn.com/20180930/a0c7317cfd0faaf2b15328e0e9a375e4.jpg)
Title: Oxidization
Post by: The Beerery on September 30, 2018, 05:36:58 pm
I am at 3% boil off for a 60 minute boil.  I boil out of a 3”tc with a boil coil at 45%.  Zero dms issues. PH is also a major factor in DMS. Get those pH’s in the 5.4 range for the bulk of the boil.

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Title: Re: Oxidization
Post by: hopfenundmalz on September 30, 2018, 06:09:21 pm
narcout said “it's pretty unlikely you're going to notice any ill effects from small scale, additional oxygenation on the hot side.” Emphasis on hot side.

I think that’s right. There are definitely “noticeable effects from oxygen during other processes.” But, most of those effects are from cold side oxidation if you aren’t doing low oxygen brewing (narcout’s assumption).

I've seen at least one instance that proves my point.  It is possible on the hot side whether you brew low oxygen or not.

Can you please elaborate?

I did say it was good practice to avoid HSA regardless of whether one is brewing LODO.

Yes, you did, and there's no doubt of that.  I have seenm someone have trouble with large amounts of air in their runoff lineof and the beer was badly oxidized despite the rest of the processes being good.  Not conclusive, of course, but an interesting data point.
Years back Vinnie C had said to remove all of the air from your hoses. That was good advice.
Title: Re: Oxidization
Post by: ynotbrusum on September 30, 2018, 07:02:49 pm
If you do a recirc HERMS, you simply start the recirc before immersing the return line/halo.  Then with a tight system, you should be good to go.  After a couple years of low Ox brewing, I tried a Helles without the low Ox methods and found it to be heavily oxidized, almost as badly as the German beers I buy at the local bottle shop.

I am spoiled, I know, but it truly is readily noticeable and I am not being a beer snob - if I could get fresh enough German beers, I would happily buy them.  I go back frequently to buy German beers that are as fresh as I can get and while I am always hopeful, oxidation typically is very noticeable.  I run them by non-BJCP friends to blindly ask them what they think and “lack of freshness” is the most frequent comment when the commercial beers are sampled as compared to my Low Ox versions.  YMMV and I wish it weren’t so in my experiences.
Title: Re: Oxidization
Post by: denny on October 01, 2018, 08:35:01 am
narcout said “it's pretty unlikely you're going to notice any ill effects from small scale, additional oxygenation on the hot side.” Emphasis on hot side.

I think that’s right. There are definitely “noticeable effects from oxygen during other processes.” But, most of those effects are from cold side oxidation if you aren’t doing low oxygen brewing (narcout’s assumption).

I've seen at least one instance that proves my point.  It is possible on the hot side whether you brew low oxygen or not.

Can you please elaborate?

I did say it was good practice to avoid HSA regardless of whether one is brewing LODO.

Yes, you did, and there's no doubt of that.  I have seenm someone have trouble with large amounts of air in their runoff lineof and the beer was badly oxidized despite the rest of the processes being good.  Not conclusive, of course, but an interesting data point.
Years back Vinnie C had said to remove all of the air from your hoses. That was good advice.

This was a case of someone using a way oversized hose and not getting a tight connection.
Title: Re: Oxidization
Post by: Big Monk on October 03, 2018, 06:40:39 pm
It seems there is a great deal of discussion pertaining to Hot Side vs. Cold Side of the brewing process.  Instead, shouldn’t the discussion be Pre-Aeration and Post-Fermentation?  Perhaps I simply don’t understand the conversation.  But we want oxygen in the wort when we pitch.  Then, we work to avoid inclusion of oxygen after fermentation.

I want as much splashing as possible when I pump my wort from the BC through my plate cooler and into the fermenter; this can only help fermentation.

So why would oxygen on the hot side be of any concern?  Am I missing something?

You want a controlled addition of oxygen at the right time, i.e. in cooled, pre-fermentation wort. Oxygen is orders of magnitude less reactive with the wort  at pitching temperatures than at mash temps. The rates at which oxygen will affect a chilled wort are such that an active pitch of yeast will chew through it before it could ever cause any damage.
Title: Re: Oxidization
Post by: goose on October 04, 2018, 07:50:08 am
Although I agree that appropriate steps should be taken to minimize oxygen uptake during the mash, runoff, and boil steps of the brewing process, I remember a paper that was presented at the 2014 Homebrew Con in Grand Rapids about HSA.  It said in a nut shell that it was not as big a problem as originally thought.  They tested an ESB that was brewed using good brewing practices (the control beer) and also where they oxygenated the hell out of the wort during mash and boil stages.  They evaluated the beers when fresh, after 10 weeks in the bottle, and after 20 weeks in the bottle to determine if the excessive O2 had any adverse effects when compared to the control beer.  Mind you, I would never try to repeat this experiment but the results were interesting.  We also got to sample some of the control beer and the 'excessively oxygenated" beers so that we could see for ourselves.

The link to the paper is:  https://www.homebrewersassociation.org/attachments/presentations/pdf/2014/Effects%20of%20Hot%20Side%20Aeration%20of%20Wort,%20Mash%20and%20Sparge%20Water.pdf

There is also a live recording of the seminar on the AHA web site.

I am sure that noticeable effects could appear after longer aging but this was an interesting experiment.  Of course, YMMV.  Denny, maybe you could weigh in on this a bit more since you have had a lot more experience with oxidized beers.
Title: Re: Oxidization
Post by: Big Monk on October 04, 2018, 08:50:59 am
Although I agree that appropriate steps should be taken to minimize oxygen uptake during the mash, runoff, and boil steps of the brewing process, I remember a paper that was presented at the 2014 Homebrew Con in Grand Rapids about HSA.  It said in a nut shell that it was not as big a problem as originally thought.  They tested an ESB that was brewed using good brewing practices (the control beer) and also where they oxygenated the hell out of the wort during mash and boil stages.  They evaluated the beers when fresh, after 10 weeks in the bottle, and after 20 weeks in the bottle to determine if the excessive O2 had any adverse effects when compared to the control beer.  Mind you, I would never try to repeat this experiment but the results were interesting.  We also got to sample some of the control beer and the 'excessively oxygenated" beers so that we could see for ourselves.

The link to the paper is:  https://www.homebrewersassociation.org/attachments/presentations/pdf/2014/Effects%20of%20Hot%20Side%20Aeration%20of%20Wort,%20Mash%20and%20Sparge%20Water.pdf

There is also a live recording of the seminar on the AHA web site.

I am sure that noticeable effects could appear after longer aging but this was an interesting experiment.  Of course, YMMV.  Denny, maybe you could weigh in on this a bit more since you have had a lot more experience with oxidized beers.

The problem with experiments that attempt to analyze the affect of HSA is that their control beer is really not a control beer. If you mash in with oxygen saturated water, and are careful on the cold side, the resulting beers won't differ significantly, i.e. the beer is already oxygenated heavily at mash in.

Remove the Low Oxygen/Standard argument for a second and just contemplate what a real control beer for an HSA experiment would be and realize that it would two separate but identical batches, with one devoid of oxygen throughout the process and one created just as in the presentation posted above. Then compare the results.
Title: Re: Oxidization
Post by: goose on October 04, 2018, 10:03:56 am
Although I agree that appropriate steps should be taken to minimize oxygen uptake during the mash, runoff, and boil steps of the brewing process, I remember a paper that was presented at the 2014 Homebrew Con in Grand Rapids about HSA.  It said in a nut shell that it was not as big a problem as originally thought.  They tested an ESB that was brewed using good brewing practices (the control beer) and also where they oxygenated the hell out of the wort during mash and boil stages.  They evaluated the beers when fresh, after 10 weeks in the bottle, and after 20 weeks in the bottle to determine if the excessive O2 had any adverse effects when compared to the control beer.  Mind you, I would never try to repeat this experiment but the results were interesting.  We also got to sample some of the control beer and the 'excessively oxygenated" beers so that we could see for ourselves.

The link to the paper is:  https://www.homebrewersassociation.org/attachments/presentations/pdf/2014/Effects%20of%20Hot%20Side%20Aeration%20of%20Wort,%20Mash%20and%20Sparge%20Water.pdf

There is also a live recording of the seminar on the AHA web site.

I am sure that noticeable effects could appear after longer aging but this was an interesting experiment.  Of course, YMMV.  Denny, maybe you could weigh in on this a bit more since you have had a lot more experience with oxidized beers.

The problem with experiments that attempt to analyze the affect of HSA is that their control beer is really not a control beer. If you mash in with oxygen saturated water, and are careful on the cold side, the resulting beers won't differ significantly, i.e. the beer is already oxygenated heavily at mash in.

Remove the Low Oxygen/Standard argument for a second and just contemplate what a real control beer for an HSA experiment would be and realize that it would two separate but identical batches, with one devoid of oxygen throughout the process and one created just as in the presentation posted above. Then compare the results.

That would be a good follow-up experiment.  Obviously, there have been changes in procedures since 2014 and there is more information out there but for general homebrewing (if you are not a fierce competition brewer), I think that we might be over-analyzing things.  I don't dispute your post, I am just thinking, RDWHAHB.  If your beer tastes good to you and your friends, all is good with the world.  If you start having oxidation problems, then it's time to take a look at your process.
Title: Re: Oxidization
Post by: denny on October 04, 2018, 10:05:50 am
Good on ya, Goose.
Title: Re: Oxidization
Post by: Big Monk on October 04, 2018, 01:04:37 pm
Although I agree that appropriate steps should be taken to minimize oxygen uptake during the mash, runoff, and boil steps of the brewing process, I remember a paper that was presented at the 2014 Homebrew Con in Grand Rapids about HSA.  It said in a nut shell that it was not as big a problem as originally thought.  They tested an ESB that was brewed using good brewing practices (the control beer) and also where they oxygenated the hell out of the wort during mash and boil stages.  They evaluated the beers when fresh, after 10 weeks in the bottle, and after 20 weeks in the bottle to determine if the excessive O2 had any adverse effects when compared to the control beer.  Mind you, I would never try to repeat this experiment but the results were interesting.  We also got to sample some of the control beer and the 'excessively oxygenated" beers so that we could see for ourselves.

The link to the paper is:  https://www.homebrewersassociation.org/attachments/presentations/pdf/2014/Effects%20of%20Hot%20Side%20Aeration%20of%20Wort,%20Mash%20and%20Sparge%20Water.pdf

There is also a live recording of the seminar on the AHA web site.

I am sure that noticeable effects could appear after longer aging but this was an interesting experiment.  Of course, YMMV.  Denny, maybe you could weigh in on this a bit more since you have had a lot more experience with oxidized beers.

The problem with experiments that attempt to analyze the affect of HSA is that their control beer is really not a control beer. If you mash in with oxygen saturated water, and are careful on the cold side, the resulting beers won't differ significantly, i.e. the beer is already oxygenated heavily at mash in.

Remove the Low Oxygen/Standard argument for a second and just contemplate what a real control beer for an HSA experiment would be and realize that it would two separate but identical batches, with one devoid of oxygen throughout the process and one created just as in the presentation posted above. Then compare the results.

That would be a good follow-up experiment.  Obviously, there have been changes in procedures since 2014 and there is more information out there but for general homebrewing (if you are not a fierce competition brewer), I think that we might be over-analyzing things.  I don't dispute your post, I am just thinking, RDWHAHB.  If your beer tastes good to you and your friends, all is good with the world.  If you start having oxidation problems, then it's time to take a look at your process.

I'm inclined to agree with you WRT the simple fact that if you enjoy the beer you make then over analyzing it is a solution in search of a problem.

If, however, we want to discuss how to structure a valid comparison between two beers that analyzes a single variable such as HSA at a certain point in the process, then you have to get in the weeds a little bit and make the distinction I did.

In general, the most devastating type of oxidation is on the cold side, but there is an incredible amount of nuance and degrees of damage on the hot side as well. It's just a matter of what you are trying to determine from an experimental point of view.

You are absolutely right though when you say that ultimately it's the individual brewer who has to decide when and where improvements are warranted.
Title: Re: Oxidization
Post by: hopfenundmalz on October 04, 2018, 01:30:43 pm
An ESB might be the wrong style for this. Malts kilned to 3+ lovibond have little of the compound left according to what Ricardo Fritche presented on the AHA web session.

A Helles or Pils would be the beer to test it on.
Title: Re: Oxidization
Post by: tommymorris on October 04, 2018, 01:36:03 pm
An ESB might be the wrong style for this. Malts kilned to 3+ lovibond have little of the compound left according to what Ricardo Fritche presented on the AHA web session.

A Helles or Pils would be the beer to test it on.
Which compound do you mean?
Title: Re: Oxidization
Post by: ynotbrusum on October 04, 2018, 01:44:36 pm
An ESB might be the wrong style for this. Malts kilned to 3+ lovibond have little of the compound left according to what Ricardo Fritche presented on the AHA web session.

A Helles or Pils would be the beer to test it on.
Which compound do you mean?

Trans 2 nonenal is the staling compound typically referenced.
Title: Re: Oxidization
Post by: The Beerery on October 04, 2018, 01:53:16 pm
LOX.
Title: Re: Oxidization
Post by: denny on October 04, 2018, 01:57:38 pm
LOX.

Love it on bagels with cream cheese!
Title: Re: Oxidization
Post by: ynotbrusum on October 04, 2018, 02:05:37 pm
LOX.

Lipoxygenase, see here:

https://en.m.wikipedia.org/wiki/Lipoxygenase

Title: Re: Oxidization
Post by: tommymorris on October 04, 2018, 02:06:29 pm
Thanks. Maybe I should brew more with pale ale malt. :)
Title: Re: Oxidization
Post by: BrewBama on October 04, 2018, 02:17:36 pm
Thanks. Maybe I should brew more with pale ale malt. :)

I recall Brulosophy did a test between Pils and Pale malt in the same recipe and no one could tell the difference. Who knows that may not be a bad way to go.


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Title: Re: Oxidization
Post by: denny on October 04, 2018, 02:28:07 pm
Thanks. Maybe I should brew more with pale ale malt. :)

I recall Brulosophy did a test between Pils and Pale malt in the same recipe and no one could tell the difference. Who knows that may not be a bad way to go.


Sent from my iPad using Tapatalk

It wpould depend on a beer.  Might not be detectable in a pale ale or IPA, but likely could in a pils, helles, or something light.
Title: Re: Oxidization
Post by: Slowbrew on October 04, 2018, 03:02:28 pm
LOX.

Main component of rocket fuel.  Liquid Oxygen.  ::)

Paul

 ;D
Title: Re: Oxidization
Post by: hopfenundmalz on October 04, 2018, 03:12:23 pm
LOX.

Main component of rocket fuel.  Liquid Oxygen.  ::)

Paul

 ;D
It is the oxidizer for the other fuel component.
Title: Re: Oxidization
Post by: hopfenundmalz on October 04, 2018, 03:14:51 pm
I had to find Ricardo's presentation. Busy today.

https://www.homebrewersassociation.org/archived-zymurgy-live/hot-side-oxidation-fact-fiction/
Title: Re: Oxidization
Post by: BrewBama on October 04, 2018, 03:46:43 pm
Thanks. Maybe I should brew more with pale ale malt. :)

I recall Brulosophy did a test between Pils and Pale malt in the same recipe and no one could tell the difference. Who knows that may not be a bad way to go.


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It wpould depend on a beer.  Might not be detectable in a pale ale or IPA, but likely could in a pils, helles, or something light.

Here it is. Looks like it was a Cal Common. http://brulosophy.com/2017/08/28/grain-comparison-pale-malt-2-row-vs-pilsner-malt-exbeeriment-results/


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Title: Re: Oxidization
Post by: denny on October 04, 2018, 04:43:34 pm
Thanks. Maybe I should brew more with pale ale malt. :)

I recall Brulosophy did a test between Pils and Pale malt in the same recipe and no one could tell the difference. Who knows that may not be a bad way to go.


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It wpould depend on a beer.  Might not be detectable in a pale ale or IPA, but likely could in a pils, helles, or something light.

Here it is. Looks like it was a Cal Common. http://brulosophy.com/2017/08/28/grain-comparison-pale-malt-2-row-vs-pilsner-malt-exbeeriment-results/


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Yep, I could see that for that style it wouldn't make a lot of difference. Might be different for something that used only pils malt, but I wouldn't swear to it til I tried it.
Title: Re: Oxidization
Post by: Hersey on October 05, 2018, 09:35:48 am
Interesting,  I thought a more rigorous boil was desired.  I'll have to turn my burner down and give it a try.

The idea of a long, vigorous boil was to drive off DMS.  In fact, it takes at least 30 minutes on heat to convert the DMS precursor,  SMM, into DMS,  after which just a few minutes of an open boil with lots of rolling and bubbling will drive it off.  BUT.  It is very rare today to find a malt that contains the precursor, although it was common in the palest Pilsner malts decades ago, whence the old advice.  For all other purposes you can keep the lid mostly on, allowing you to reduce the heat, and just maintain a simmer providing the good rolling circulation which you need to coagulate protein and well utilize your hops. Then lid off and blast it for a bit, there are still other volatiles fo blow off. One trick I like for this is to heat the kettle asymmetrically. This will create a lot of movement and turbulence. (Here's an indicator:  if your boil off is under 10%, even as low as 6%, you're probably doing well on the thermal stress.  Above that, and especially when you hit 12%, wort will taste stale and get staler faster.) 

(I had a long brewing hiatus too, in the late 90s to early 00s, and it seemed not much had changed.  In the last 10 years, it seems everything we knew has been upended!)

Good to know!  I've got a cover for my bk but generally haven't used it except to keep debris from falling in if it was windy etc.  In years past I did slower gentle boils and things are starting to come back to me but still much has changed just in the time I wasn't brewing.
Title: Re: Oxidization
Post by: KellerBrauer on October 06, 2018, 06:43:18 am
This has been a very interesting subject indeed.  However, my opinion is that way too much emphasis has been placed on it.  Unless one is brewing in a vacuum (literally) the inclusion of oxygen into the process is inevitable.  I further believe it’s most important to minimize the inclusion of oxygen post fermentation than it is pre fermentation.  I think, after reading all the expert opinions in this thread, that oxygen inclusion, preboil, seems to be a major effort in futility.
Title: Re: Oxidization
Post by: Big Monk on October 06, 2018, 06:51:27 am
This has been a very interesting subject indeed.  However, my opinion is that way too much emphasis has been placed on it.  Unless one is brewing in a vacuum (literally) the inclusion of oxygen into the process is inevitable.  I further believe it’s most important to minimize the inclusion of oxygen post fermentation than it is pre fermentation.  I think, after reading all the expert opinions in this thread, that oxygen inclusion, preboil, seems to be a major effort in futility.

It’s actually extremely easy to exclude oxygen throughout the process but the discussion of how and why is outside the bounds of this thread.

I think everyone can agree, as always, on the importance of cold side oxygen exclusion.
Title: Re: Oxidization
Post by: wobdee on October 06, 2018, 03:15:49 pm
It seems there is a great deal of discussion pertaining to Hot Side vs. Cold Side of the brewing process.  Instead, shouldn’t the discussion be Pre-Aeration and Post-Fermentation?  Perhaps I simply don’t understand the conversation.  But we want oxygen in the wort when we pitch.  Then, we work to avoid inclusion of oxygen after fermentation.

I want as much splashing as possible when I pump my wort from the BC through my plate cooler and into the fermenter; this can only help fermentation.

So why would oxygen on the hot side be of any concern?  Am I missing something?

You want a controlled addition of oxygen at the right time, i.e. in cooled, pre-fermentation wort. Oxygen is orders of magnitude less reactive with the wort  at pitching temperatures than at mash temps. The rates at which oxygen will affect a chilled wort are such that an active pitch of yeast will chew through it before it could ever cause any damage.
To be safe ive gone to a vitality starter rather than relying on oxygenating the wort. Im not so sure that the yeast will take care of the O2 in the wort prior to it doing some damage. Ive read that it takes yeast 30 minutes or more to use up the O2 in wort. This seems like a long time to me where there may be some damage happening?
Title: Re: Oxidization
Post by: ynotbrusum on October 06, 2018, 07:23:36 pm
Here you go :

https://www.morebeer.com/articles/how_yeast_use_oxygen

Pretty much answers the question.
Title: Re: Oxidization
Post by: Robert on October 06, 2018, 11:23:09 pm
Here you go :

https://www.morebeer.com/articles/how_yeast_use_oxygen

Pretty much answers the question.
Thanks for pointing out this excellent summary.   It is important to separate the two very distinct functions oxygen performs in yeast metabolism.   If one could get past all the recent screaming of "Crabtree! Crabtree!  Yeast doesn't respire!" it would become quite clear why actual, practical experience demonstrates that a starter on a stir plate, exchanging CO2 for O2,  produces a far greater mass of far healthier yeast, leading to better ordered fermentations, better beer,  and yeast better prepared for repitching, and why it is important to decant the liquid containing undesirable products no matter how you grow your starter.  Common sense may come round yet again.  (Standard disclaimer, YMMV, it's all a crapshoot with homebrew.)
Title: Re: Oxidization
Post by: mabrungard on October 07, 2018, 07:15:36 am
It’s actually extremely easy to exclude oxygen throughout the process but the discussion of how and why is outside the bounds of this thread.

I think everyone can agree, as always, on the importance of cold side oxygen exclusion.

I've incorporated many refinements to my methods and equipment to reduce oxygen uptake on both the hot and cold sides. For some styles (light malty), I find that it definitely makes a difference. But not so much for others.

The ease with which I incorporated those measures was probably increased since I already ran a RIMS. For brewers employing more mash mixing, it may not be nearly as easy and they are less likely to note a difference even in those beer styles that benefit.

At a minimum, I strongly encourage brewers to focus on eliminating post-fermentation oxygen contact during transfer and packaging. That definitely improves the longevity of your beers.
Title: Re: Oxidization
Post by: Big Monk on October 07, 2018, 09:26:06 am
I've incorporated many refinements to my methods and equipment to reduce oxygen uptake on both the hot and cold sides. For some styles (light malty), I find that it definitely makes a difference. But not so much for others.

I will say that I have a very limited scope of beers brewed. I do Trappist “style” ales, Pale Ale, 9% Imperial Stout and Brown Ale. I’ve noticed the difference in all of them, especially my Trappist beers. Overall I agree with you though. For many this may be another tool in the toolbox to nail paler beers.

The ease with which I incorporated those measures was probably increased since I already ran a RIMS. For brewers employing more mash mixing, it may not be nearly as easy and they are less likely to note a difference even in those beer styles that benefit.

I disagree here. For single infusion without recirc, gentle stirring and Metabisulfite are your friend. We have a number of very successful single infusion brewers with very simple cooler rigs and a spoon for stirring.

At a minimum, I strongly encourage brewers to focus on eliminating post-fermentation oxygen contact during transfer and packaging. That definitely improves the longevity of your beers.

Absolutely no one in this day and age should disagree with you here.
Title: Re: Oxidization
Post by: denny on October 07, 2018, 09:44:30 am
Here you go :

https://www.morebeer.com/articles/how_yeast_use_oxygen

Pretty much answers the question.
Thanks for pointing out this excellent summary.   It is important to separate the two very distinct functions oxygen performs in yeast metabolism.   If one could get past all the recent screaming of "Crabtree! Crabtree!  Yeast doesn't respire!" it would become quite clear why actual, practical experience demonstrates that a starter on a stir plate, exchanging CO2 for O2,  produces a far greater mass of far healthier yeast, leading to better ordered fermentations, better beer,  and yeast better prepared for repitching, and why it is important to decant the liquid containing undesirable products no matter how you grow your starter.  Common sense may come round yet again.  (Standard disclaimer, YMMV, it's all a crapshoot with homebrew.)

I just haven't found your concerns to be anything other than theoretical.  I have found non stir plate starters, pitched with the starter wort to make beer that is at least equivalent to what I was doing before.  There's common sense, and there's practical experience.  YMMV, but again I think you're painting with too broad a brush. 
Title: Re: Oxidization
Post by: klickitat jim on October 07, 2018, 10:10:47 am
Here you go :

https://www.morebeer.com/articles/how_yeast_use_oxygen

Pretty much answers the question.
Thanks for pointing out this excellent summary.   It is important to separate the two very distinct functions oxygen performs in yeast metabolism.   If one could get past all the recent screaming of "Crabtree! Crabtree!  Yeast doesn't respire!" it would become quite clear why actual, practical experience demonstrates that a starter on a stir plate, exchanging CO2 for O2,  produces a far greater mass of far healthier yeast, leading to better ordered fermentations, better beer,  and yeast better prepared for repitching, and why it is important to decant the liquid containing undesirable products no matter how you grow your starter.  Common sense may come round yet again.  (Standard disclaimer, YMMV, it's all a crapshoot with homebrew.)

I just haven't found your concerns to be anything other than theoretical.  I have found non stir plate starters, pitched with the starter wort to make beer that is at least equivalent to what I was doing before.  There's common sense, and there's practical experience.  YMMV, but again I think you're painting with too broad a brush.
I wish we could use two different terms for what everyone calls "starters". To me a "starter" simply starts the yeast, gets it out of dormancy, begins its phases of activity. What many people call a "starter" is probably a propagator...  if the "starter" completes or nearly completes the yeast life cycle, in my book it's propagation not a starter, and unless it's a properly handled drinkable beer, it ought to be decanted and discarded.
Title: Re: Oxidization
Post by: Robert on October 07, 2018, 11:19:23 am
Here you go :

https://www.morebeer.com/articles/how_yeast_use_oxygen

Pretty much answers the question.
Thanks for pointing out this excellent summary.   It is important to separate the two very distinct functions oxygen performs in yeast metabolism.   If one could get past all the recent screaming of "Crabtree! Crabtree!  Yeast doesn't respire!" it would become quite clear why actual, practical experience demonstrates that a starter on a stir plate, exchanging CO2 for O2,  produces a far greater mass of far healthier yeast, leading to better ordered fermentations, better beer,  and yeast better prepared for repitching, and why it is important to decant the liquid containing undesirable products no matter how you grow your starter.  Common sense may come round yet again.  (Standard disclaimer, YMMV, it's all a crapshoot with homebrew.)

I just haven't found your concerns to be anything other than theoretical.  I have found non stir plate starters, pitched with the starter wort to make beer that is at least equivalent to what I was doing before.  There's common sense, and there's practical experience.  YMMV, but again I think you're painting with too broad a brush.
I was referring to the line of arguement I've encountered that "since yeast don't respire, a stir plate couldn't possibly help, so you shouldn't ever use it" while there's plenty of published and practical evidence to the contrary.  This explains why. Continuous gas exchange can improve growth and health, and it has nothing to do with respiration.   So it can be useful, but that depends on lots of other aspects of your process.  I personally rarely use a stir plate, my starters are usually too big, so just O2 at the start.  But I'm still in the camp going for maximum cell count and long term health, because I'm not pitching at high kräusen, just doesn't fit my brew schedule.  If you are, then you can't decant, so you want to avoid excessive aeration of the starter to avoid pitching off flavors with your yeast. If you plan to repitch, other  concerns are involved.  There's no single optimal method, but no wrong one either. The article provides insight into some subtleties than can help you decide on what aeration practices best suit your own yeast handling and fermentation procedures.  I think it's a good resource.   I'll have to reread it at an earlier hour of the day, saw that post on my way to bed.

I like Jim's point a lot.  There are two models here, as there are two stages of yeast growth in breweries:  lab propagation, stepping up at high kräusen,  and brewery propagation, successive completed and decanted batches.  The "vitality starter"  follows the lab model, the decanted "starter" the brewery model.  Distinguishing between the two, with their different goals, would eliminate confusion about the "right" way to conduct them.  FWIW I have always personally referred to my procedure as "propagation," not a "starter."  But in general conversation that subtlety gets lost.
Title: Re: Oxidization
Post by: denny on October 07, 2018, 11:28:09 am
Here you go :

https://www.morebeer.com/articles/how_yeast_use_oxygen

Pretty much answers the question.
Thanks for pointing out this excellent summary.   It is important to separate the two very distinct functions oxygen performs in yeast metabolism.   If one could get past all the recent screaming of "Crabtree! Crabtree!  Yeast doesn't respire!" it would become quite clear why actual, practical experience demonstrates that a starter on a stir plate, exchanging CO2 for O2,  produces a far greater mass of far healthier yeast, leading to better ordered fermentations, better beer,  and yeast better prepared for repitching, and why it is important to decant the liquid containing undesirable products no matter how you grow your starter.  Common sense may come round yet again.  (Standard disclaimer, YMMV, it's all a crapshoot with homebrew.)

I just haven't found your concerns to be anything other than theoretical.  I have found non stir plate starters, pitched with the starter wort to make beer that is at least equivalent to what I was doing before.  There's common sense, and there's practical experience.  YMMV, but again I think you're painting with too broad a brush.
I wish we could use two different terms for what everyone calls "starters". To me a "starter" simply starts the yeast, gets it out of dormancy, begins its phases of activity. What many people call a "starter" is probably a propagator...  if the "starter" completes or nearly completes the yeast life cycle, in my book it's propagation not a starter, and unless it's a properly handled drinkable beer, it ought to be decanted and discarded.

But isn't the same thing true of the wort no matter what you call it?  Maybe I'm misunderstanding you, but are you saying it's OK to pitch wort from a starter, but not a propagator?
Title: Re: Oxidization
Post by: Robert on October 07, 2018, 11:33:07 am
^^^^
If it tastes ok, sure, pitch it.  But (this is referenced in the article in question) if you continuously aerate the propagation,  which may be advisable,  it's not going to taste good.  So decant.  Case by case.
Title: Re: Oxidization
Post by: denny on October 07, 2018, 11:39:32 am
^^^^
If it tastes ok, sure, pitch it.  But (this is referenced in the article in question) if you continuously aerate the propagation,  which may be advisable,  it's not going to taste good.  So decant.  Case by case.

I agree that if you continuously aerate it won't taste good and you shouldn't pitch it.  But I don't believe you were that specific in your previous statement.  Sounds like we're in agreement.
Title: Re: Oxidization
Post by: narcout on October 07, 2018, 03:05:13 pm
I was referring to the line of arguement I've encountered that "since yeast don't respire, a stir plate couldn't possibly help, so you shouldn't ever use it" while there's plenty of published and practical evidence to the contrary.

Maybe I've missed it, but I don't think I've heard anyone say that.

The Crabtree Effect doesn't mean yeast don't utilize oxygen to synthesize sterols, etc. or that oxygen isn't beneficial.
Title: Re: Oxidization
Post by: hmbrewing on October 08, 2018, 08:24:13 am
I'm just not at that part of my "brewing career" that I want to worry about HSA. I'm not saying I splash the hell out of my wort. I take measures to ensure my recirc tube is below the mash level and small stuff like that. But, beyond that - I just can't see complicating my brew day. The beer that I brew, keg, and enjoy is just too delicious to justify complicating it at this time. Could it be better if I watch my HSA? I don't know, maybe. But I've spent time on changes like building water from distilled and controlling fermentation temperatures to within 1 degree. These 2 changes alone have greatly improved the quality of my beer but I also recognized that I needed to make those changes due to inconsistency from batch to batch. As of right now I'm not picking up on anything that makes me want to start worrying about HSA.

I also only brew 2.5g batches. It's possible this whole HSA thing is more concerning at larger scales. I don't know. Not an expert on this.
Title: Re: Oxidization
Post by: Big Monk on October 08, 2018, 08:25:55 am
I'm just not at that part of my "brewing career" that I want to worry about HSA. I'm not saying I splash the hell out of my wort. I take measures to ensure my recirc tube is below the mash level and small stuff like that. But, beyond that - I just can't see complicating my brew day. The beer that I brew, keg, and enjoy is just too delicious to justify complicating it at this time. Could it be better if I watch my HSA? I don't know, maybe. But I've spent time on changes like building water from distilled and controlling fermentation temperatures to within 1 degree. These 2 changes alone have greatly improved the quality of my beer but I also recognized that I needed to make those changes due to inconsistency from batch to batch. As of right now I'm not picking up on anything that makes me want to start worrying about HSA.

I also only brew 2.5g batches. It's possible this whole HSA thing is more concerning at larger scales. I don't know. Not an expert on this.

Honestly, that's right where you should be. If you like the beer you make, why change it? If you are looking for improvement, then you can investigate other techniques.
Title: Re: Oxidization
Post by: Robert on October 08, 2018, 09:03:01 am
Actually I think it has more potential impact on smaller scales, because of increased surface area to volume among other things maybe.   But its impact is certainly dependent on style, that is ingredients, the rest of the process, desired outcomes and so on.  So yeah, if the beer you brew suggests you don't need to worry about it,  you should probably listen to your beer.  Cheers.