27 replies to this topic

[ranagel99]

I brew 5.5 gallon batches chill with a SS Immersion Chiller. In the past I have always stirred vigoursly right after flame out to try to help cool my wort as fast as possible. I then realized that I could be aerateing too much at high temperatures. What should my concerns be here and at what temp should I be okay to vigoursly stirr vs gently stirr? Thanks

[jayb151]

I brew 5.5 gallon batches chill with a SS Immersion Chiller. In the past I have always stirred vigoursly right after flame out to try to help cool my wort as fast as possible. I then realized that I could be aerateing too much at high temperatures. What should my concerns be here and at what temp should I be okay to vigoursly stirr vs gently stirr? Thanks

I think the question here is do you notice any off flavors? i would only change my process if i wanted to decrease the likelihood on unfavorable results. That said, I gently stir my wort until it gets cool, then I start to really agitate it.

[CaptRon]

Someone here posted a while back that they didn't think that hot side aeration was really anything to worry about. I myself have never noticed anything different since I started stirring for a whirlpool after flameout. I'm curious to see what other responses come from this though.

[stellarbrew]

I personally wouldn't have any worries about stirring fairly vigorously, just so long as you aren't splashing it when you stir.I used to worry much more about hot side aeration, before I heard an expert discuss how well the yeast actually does clean up the oxidized compounds during fermentation. According to him, the yeast does remove many of the products of HSA that some people had asserted were not scrubbed out during fermentation.Edit: I looked back and saw where I had heard that. It was from a Brew Strong discussion Jamil Z. and John P. had with Dr. Charles Bamforth, on the Brewing Network. https://thebrewingne...k.com/shows/475

Edited by stellarbrew, 01 October 2009 - 03:11 PM.

[MtnBrewer]

I personally wouldn't have any worries about stirring fairly vigorously, just so long as you aren't splashing it when you stir.I used to worry much more about hot side aeration, before I heard an expert discuss how well the yeast actually does clean up the oxidized compounds during fermentation. According to him, the yeast does remove many of the products of HSA that some people had asserted were not scrubbed out during fermentation.Edit: I looked back and saw where I had heard that. It was from a Brew Strong discussion Jamil Z. and John P. had with Dr. Charles Bamforth, on the Brewing Network. https://thebrewingne...k.com/shows/475

Hmmm....I'm not sure I buy that. If that were true, there'd be no such thing as oxidized beer.

[ColdAssHonky]

Hmmm....I'm not sure I buy that. If that were true, there'd be no such thing as oxidized beer.

Does the oxidized taste in a finished beer come from pre-ferment oxidization or improper handling after fermentation is complete?

[zymot]

Over on the board of green, oldfart did an experiment. He specifically introduced HSA to a beer. IIRC The taste test results showed that HSA is another source of homebrewers anxiety syndrome. Nobody was willing to declare HSA a myth, but it does seem to be exagerated on how easy it is to induce and teh negative results seem to be exagerated.Many times I have watched a show about professionals brewing beer and it is clear that they are not very distracted by HSA.I take reasonable care to avoid inducing HSA when I can, but I do not go about my brew day treating HSA as a disaster waiting to happen.

[CaptRon]

Hmmm....I'm not sure I buy that. If that were true, there'd be no such thing as oxidized beer.

Does the oxidized taste in a finished beer come from pre-ferment oxidization or improper handling after fermentation is complete?

I would think that the beer would be more susceptible to oxidation after fermenting takes place. Otherwise oxygenating the pre-fermented wort would always be a problem.

[MtnBrewer]

Does the oxidized taste in a finished beer come from pre-ferment oxidization or improper handling after fermentation is complete?

Could be either one. Oxidation is oxidation. It's more severe on the hot side since it occurs much faster at higher temperatures.

[MtnBrewer]

Over on the board of green, oldfart did an experiment. He specifically introduced HSA to a beer. IIRC The taste test results showed that HSA is another source of homebrewers anxiety syndrome. Nobody was willing to declare HSA a myth, but it does seem to be exaggerated on how easy it is to induce and the negative results seem to be exaggerated.

Actually, oldfart's experiment showed just the opposite. After a couple of months there was pretty severe oxidation of the beer. This was according to Denny, who was oldfart's taste tester.

[MtnBrewer]

I would think that the beer would be more susceptible to oxidation after fermenting takes place. Otherwise oxygenating the pre-fermented wort would always be a problem.

No, it's more susceptible when the wort is hot because oxidation occurs pretty much instantly at those higher temperatures. It doesn't cause a problem prior to fermentation because the yeast consume the oxygen before it can do any damage.

[CaptRon]

Actually, oldfart's experiment showed just the opposite. After a couple of months there was pretty severe oxidation of the beer. This was according to Denny, who was oldfart's taste tester.

So this is an easy solution...If you drink your beer quick enough, this will never be an issue.

[ColdAssHonky]

So this is an easy solution...If you drink your beer quick enough, this will never be an issue.

I'm sold.

[MtnBrewer]

So this is an easy solution...If you drink your beer quick enough, this will never be an issue.

Well yeah, that's always been the advice for beers that may have been oxidized. But it's not always practical. Sometimes, beers need to age for a while before they are at their best. Also, I think it's always a good idea to adopt your best practices for every beer. Always bring your A game, especially when the steps required are so easy. Now we all get lazy from time to time but if you just make your best practices a habit, then every beer will have good stability even if it doesn't need to. It can only make you a better brewer overall.

[stellarbrew]

Actually, oldfart's experiment showed just the opposite. After a couple of months there was pretty severe oxidation of the beer. This was according to Denny, who was oldfart's taste tester.

Although this Bamforth fellow is supposed to be one of the world's foremost experts, I can't discount what oldfart and Denny found in their experiment. I will say that Bamforth emphasized the importance of proper pitch rate, and a vigorous fermentation, in effectively scrubbing out the oxidation. I wonder if the fermentation was optimally vigorous in the mentioned experiment.

[ThroatwobblerMangrove]

I try not to agitate things very much until the wort is cool. After the first few minutes I'll usually lightly swirl my IC just to get the higher temperature wort in contact with the IC (I can tell this is helping b/c I can feel the exit side of the chiller heat up right away). I don't think I've had any problems with oxidation.

[JimNasium]

I've always been taught that introducing oxygen to post-boil wort at temps higher than 80 degrees is a bad practice. I never take the chance of stirring even below that 80 degree mark and just wait patiently for the wort to cool at it's own pace with the aide of the IC. YMMV, but I'm not big on taking that risk when I've got a lower risk alternative called patience.

[ThroatwobblerMangrove]

I've always been taught that introducing oxygen to post-boil wort at temps higher than 80 degrees is a bad practice. I never take the chance of stirring even below that 80 degree mark and just wait patiently for the wort to cool at it's own pace with the aide of the IC. YMMV, but I'm not big on taking that risk when I've got a lower risk alternative called patience.

There is a trade off actually - chilling faster has certain benefits beyond making the impatient feel better. Granted - I wouldn't go as far as to do any splashing.

[MakeMeHoppy]

Back to the original question I think a gentle stir is all that is needed anyway. You just want to keep the wort moving over the chiller coils so that they are always in contact with the hot wort. No need to stir so hard that you would be aerating the wort.

[zymot]

Actually, oldfart's experiment showed just the opposite. After a couple of months there was pretty severe oxidation of the beer. This was according to Denny, who was oldfart's taste tester.

Denny or oldfart, care to comment?I know Denny is on this board, this is no member named oldfart.