Hot Side Aeration

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Lilburgh

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I've been brewing for almost 3 years now. I started brewing with some friends who have been brewing for little awhile as well. During our brew days, which usually take place outside in one of our garages/driveways, we usually brew about 6-7 batches totaling 50+ gallons of various beers. We have made some really good beers, won some awards, and until recently, never dumped a batch of beer due to taste.

On Brew Days we like to pick and pull from each others self-perfected processes to try and improve our overall brew day efficiency. One of our biggest improvements has been our chilling process. Our initial chilling process was simply inserting a sanitized immersion chiller into the hot kettle and running tap water till wort is as low as tap water will allow. We then upgraded our process to draining 5 gallons of hot wort from the kettle into a food grade 6-7 gallon sanitized bucket, inserting immersion chiller and running tap water while at the same time vigorously running a sanitized paint stirrer in the wort using a cordless drill. When we started this process during the winter months we were able to chill wort to 70F in around 5 minutes depending on tap water temp. The summer months take about 10 minutes.

Whats the opinion of Hot Side Aeration (HSA)? My last 5 batches (2 different brew days and locations), all brewed in the summer months, using any one of 4 Mash Tuns, of 3 different Kettles, 2 different water sources, 5 different fermenters, and 5 different kegs, all are gonna be pitched due to off soapy flavors. The only consistent piece of equipment that touched all of these beers is the Chiller using our above mentioned process improvement. I read some about HSA, and the opinions are split and experiments are inconclusive.

Are there any thoughts on our process or how to eliminate possible HSA issues? We have not had an issue till recently, and while I said my 5 batches, the other 2 guys are having the same issues with their beers as well, which we think rules out fermenting location, temp, and process. Yeast and ingredient sources are different as well in each beer.

Any comments would be appreciated.

Thanks,
 
I don't believe in HSA. At least not at the homebrew scale. All the research I've done on it seems to indicate that it "could" be a problem at a commercial level where they're pumping barrels of wort through a three or four inch pipe and it's cascading ten feet into a vessel. If what you're doing has always worked before then there's no reason it should be a problem now. I'd look elsewhere.
 
Not sure that "soapy" is a product of oxidation?

I say go back to your old process and see if it goes away.
 
"Soapy" flavors occur during fermentation. It is caused by the breakdown of fatty acids that reside in the trub. When this occurs you are literally making soap. I highly doubt your equipment or setup is causing it. Either the yeast strain was highly active or it got left in the fermentor to long. Did you change any of your normal routine on the fermentation side for those batches?
 
I'm a recent convert. I used to think HSA was a myth. I read the thread linked below and the associated PDF, tried it for myself, and now I'm a believer. While I haven't seen quite the tectonic shift in my beers that others have claimed, they are better.

https://www.homebrewtalk.com/showthread.php?t=580532

With all that, it doesn't sound like HSA is your problem. But curious, what is that paint stir rod made from? And how fast are you stirring?
 
One other comment, bucketnative is correct.
HSA causes the oxidation of fatty acids which will give a "wet cardboard" taste.
The breakdown of fatty acids is what gives the "soapy" taste.

After thinking about it a little more, my guess is your new process is keeping a higher amount of trub is suspension and is carrying over to the fermentor. Just a guess but seems plausible.
 
After thinking about it a little more, my guess is your new process is keeping a higher amount of trub is suspension and is carrying over to the fermentor. Just a guess but seems plausible.

Interesting. I used to be a "dump it all in" brewer. Didn't leave anything behind in the kettle. Never got any soapy flavors.

But, this theory could coincide with using the paint stirrer. That is if more trub is making it to the fermenter because of the agitation.
 
I don't believe in HSA. At least not at the homebrew scale. All the research I've done on it seems to indicate that it "could" be a problem at a commercial level where they're pumping barrels of wort through a three or four inch pipe and it's cascading ten feet into a vessel. If what you're doing has always worked before then there's no reason it should be a problem now. I'd look elsewhere.

I approve this message!
 
I didn't know there was doubt regarding HSA, the first all grain batch I ever made was naively oversized and it took well over an hour with two immersion chillers to cool 30 gallons of wort (some guy had a huge kettle, we found a giant burner, and used a 50 gallon cooler as a mash tun). We were stirring frantically as well. The result was isobutyl alcohol- copier paper/wet cardboard. I wouldn't disturb hot wort at all until it dropped below at most 140F, but that happens pretty quick. If I were you, I'd put the chiller in your kettle for the last minute of boil, turn it on without stirring at flameout, see how low you get in 10 minutes. If you get to ~110 or below, go for your splash and stir method of you want to really hurry. If you can get to 80 in a half hour, who cares? 10 minutes is very quick; there is no benefit of that speed if you ruin beer by accomplishing it.
 
what is that paint stir rod made from? And how fast are you stirring?

Paint stirrer is just your normal Home Depot Polypropylene paint stirrer. We are pretty much stirring as fast as possible without over flowing the bucket.
 
Did you change any of your normal routine on the fermentation side for those batches?

Nothing changed with the fermentation process routine, might have gone little longer on the primary side, but a little longer would have been 3-4 weeks instead of 2-3 weeks.
 
We've recently started using a siphon to get the hot wort into our fermenting bucket. It keeps the sediment in the boiling kettle and it eliminates dumping the hot wort. We also use a double chiller method. We had a chiller immersed in a bucket of ice water which runs to our main chiller and our water is pumped from a tub of ice water. We get 10 gallons down to 70 degrees in about 15 minutes in texas
 
Paint stirrer is just your normal Home Depot Polypropylene paint stirrer. We are pretty much stirring as fast as possible without over flowing the bucket.

It's one thing to stir gently to avoid stratification, it's another to whip the beer into a froth. All I do is gently rock my chiller as I chill.
 
Is the paint stirrer food grade. Also, I don't think all food grade materials retain that rating at all temperatures. I have tried whirlpooling with a wine aerator that was food grade, but in boiling wort it deformed and melted and gave a bit of a plastic like taste to the beer. Maybe you are leaching some chemical out of the bucket or the stirrer or both.

I would just keep your wort in the BK to chill and use this to whirlpool:
http://www.norcalbrewingsolutions.com/store/Beer_Brewing_Paddle_Whirlpool_Aeration.html

I think the general consensus so far is that it is not HSA, which I agree with. It also sounds like most of the other variables have been eliminated since you do group brews. Does everyone in the group use this chilling method? Also like Spartan said you don't need to stir like a maniac (paraphrased).
 
I use a stainless steel paint stirrer/cordless drill all the time without any issues. When using my immersion chiller, I stir pretty fast, but not enough to cause any frothing of the wort.

mixer.jpg
 
Boil brewing water before blending the water with malt or sparging with it. Boiling removes dissolved oxygen. When brewing water isn't boiled inherent oxygen affects the mash during the rest period.
When wort temperature falls to 140F it absorbs the highest volume of air than at any other temperature. If the wort is being whipped up throughout the chilling process, when the wort temperature falls to 140F oxygen is absorbed at a high rate.
Crystal malt can cause issues. Crystal malt shares a bench with rancid malt and fatty acids in the malt cause issues that negatively impact the final product. High quality crystal is expensive.
 
HSA is real and it's robbing home brewed beer of some amazing flavors.

I'm drinking the LoDO Helles (https://www.homebrewtalk.com/showthread.php?t=580532) right now and it has the most amazing sweet grain flavor... nothing like any other home brew beer i've ever had.

It adds a bit more work to every batch but if they taste this much better its always worth it.
 
There's little evidence that HSA is real except for a handful of folks saying how great their beers are when they follow these Lodo methods. Sorry, but that's simply not evidence.

The Brulosophy experiment is a strong data point that HSA is a myth. We need more of these tests to get more answers.

Personally, I'm not even convinced that cold-side aeration is a problem for those of us who store the beer refrigerated. But we should keep an open mind, of course.
 
There's little evidence that HSA is real except for a handful of folks saying how great their beers are when they follow these Lodo methods. Sorry, but that's simply not evidence.

The Brulosophy experiment is a strong data point that HSA is a myth. We need more of these tests to get more answers.

Personally, I'm not even convinced that cold-side aeration is a problem for those of us who store the beer refrigerated. But we should keep an open mind, of course.

I've seen all the evidence I need from Fix, Narziss and Kunze.

The Brulosophy HSA experiment was flawed from the beginning since they dough in with oxygenated water and naturally sucked in more air during the mash with no means to scavenge it. So I can see where there was little difference between the two beers.
 
The Brulosophy experiment is a strong data point that HSA is a myth. We need more of these tests to get more answers.

Just an FYI, the Brulosophy experiment is fatally flawed. It compared one beer produced with O2 saturated water/wort to another beer produced with O2 saturated water/wort. There was no difference in the amount of oxygen the two beers were exposed to. Whipping one up and stirring like a mad man doesn't dissolve any more O2 if it's already saturated to begin with.
 
The best traditional british beers are made in brewhouses with a huge amount of HSA, so I think it really depends on what beer you are going for. If lagering/ageing then I'd certainly try and reduce it as much as possible, but for things like bitters and milds then I wouldn't worry in the slightest.
 
I have only encountered what I believe to be HSA one time, and that was when I took the whole 5 gallons right after boiling was finished and dumped in in a bucket laying on the ground while I was standing. This was a really stupid thing to do. It absolutely tasted like wet cardboard when finished, at least to me, but others couldn't taste it even when I suggested it. I will never forget that taste, and I have stirred other beers quite vigorously while cooling and never had that taste in any of those beers. I think you can get HSA if you try really hard like I did.
 
I've seen all the evidence I need from Fix, Narziss and Kunze.
But did they claim this HSA is relevant to non-mass-production brewing? Isn't it possible that the remaining yeast in our beers helps reduce kegged o2, and/or that constant refrigeration renders moot any staling effects? We don't have the same constraints as commercial brewers, so not all commercial practices are relevant, as we all agree.

The Brulosophy HSA experiment was flawed from the beginning since they dough in with oxygenated water and naturally sucked in more air during the mash with no means to scavenge it. So I can see where there was little difference between the two beers.
Not surprising that Lodo disciples dismiss the Brulosophy experiment, since they seem to be setting up Lodo as an untestable religion, where any level of O2 *at all* *anywhere* ruins the beer. This is of course pure speculation. Nobody seems to be considering WHERE the sensitive points are, and thus, what solutions give the most bang for the buck.

Here's a quote from Charlie Bamforth who has studied this extensively: (Beersmith podcast #74)
If you compare the relative magnitude of the effects of temperature on the finished beer and compare that with the magnitude of the impact of oxygen uptake in the brewhouse, there is no comparison. Keeping the beer cold is going to have a vastly, vastly, vastly bigger impact. So I'm not saying there's absolutely no impact of minimizing oxygen in the brewhouse, but compared with what's happening downstream, it is substantially less significant... If you minimize absolutely the amount of oxygen picked up in a brewhouse and didn't pay attention to what's downstream, you would see no effect whatsoever. If you have attended to everything downstream, then you may see a small, a smallish, a relatively small impact from minimizing oxygen uptake in the brewhouse. It's that way around. With flavor stability, you start at the end and work back - that's the way to do it.
Charlie is telling us that focusing on HSA is barking up the wrong tree.
 
As a side note, this HSA debate is reminiscent of the fad a few years ago where everyone screamed about yeast cell count, and how critical it is.... because that's what big breweries do. With time we now understand that cell count is only half the equation -- yeast vigor/health is equally or more important. And commercial breweries are pitching that much yeast not so much as it's needed but rather because, well, they have craploads of yeast sitting around.
 
There is far greater impact from oxygen downstream than there is upstream. The big, big lager brewers in the world use mash mixers that turn in the neighborhood of 150 RPM, which whips the mash up pretty good.

Just do what you have the time and energy for, personally, I can't be bothered with HSA and I'm certainly not going to be messing around with K-meta in my process water.
 
But did they claim this HSA is relevant to non-mass-production brewing? Isn't it possible that the remaining yeast in our beers helps reduce kegged o2, and/or that constant refrigeration renders moot any staling effects? We don't have the same constraints as commercial brewers, so not all commercial practices are relevant, as we all agree.


You are misrepresenting what the LoDO guys are claiming. Their main contribution is saying a low DO-mash will give you something a non-LODO mash will not, provided the rest of your process is also low oxygen.

The size of the brewery does come into play here. Larger breweries have a much lower surface to volume ratio than at the HB level so they get some intrinsic protection from oxygen egress through the surface of the mash. However, the big guys DO de-aerate their mash water AND they also purge the head space in the tun with either steam or nitrogen.


Not surprising that Lodo disciples dismiss the Brulosophy experiment, since they seem to be setting up Lodo as an untestable religion, where any level of O2 *at all* *anywhere* ruins the beer. This is of course pure speculation. Nobody seems to be considering WHERE the sensitive points are, and thus, what solutions give the most bang for the buck.

The LoDO 'disciples' dismiss the Brulosophy experiment because both the control and the experimental samples underwent the exact process they are saying is problematic.

I've done the LoDO and can tell you with certainty its not untestable. The smell and taste of the wort is totally different than non-DO. If you tried it, you'd be able to confirm this.



Here's a quote from Charlie Bamforth who has studied this extensively: (Beersmith podcast #74)

Charlie is telling us that focusing on HSA is barking up the wrong tree.

This is another misrepresentation. That quote says if you're cold side doesn't address oxygen then you are wasting your time (LoDO guys say the exact same thing). But if you're cold side is solid, then there is some benefit.

I think the main fault of the LODO authors is in the way they presented their paper and making comments like you'll want to dump all your non-LODO beer. You can make good beer without LODO, but you can make even better beer with it. The overall tone of the paper was also a bit elitist.
 
...This is another misrepresentation. That quote says if you're cold side doesn't address oxygen then you are wasting your time (LoDO guys say the exact same thing). But if you're cold side is solid, then there is some benefit.


Charlie's quote speaks for itself. Keeping the beer refrigerated is "vastly, vastly, vastly" more important than *all* the O2 uptake in the brew house (not just mash). Clearly, mash O2 is way down the list. Concluding that mash O2 is still important sounds like the guy to whom the girl says: "I wouldn't marry you if you were the last man on earth!" to which the guy responds "So you're saying I have a chance." ;)

The most reasonable working assumption for us is that keeping our beer refrigerated and minimizing o2 in the keg/bottle are the goals. Once you've done that, would these LODO practices have any more impact? LODO guys don't know -- it's total speculation. Worse, they don't seem to care. And that's what's so disgraceful about that "interesting PDF."
 
I think the tone of the paper gets things off on the wrong foot with people, myself being one of those people. LODO as a whole also seems to encompass a few concepts which I think creates some confusion.
Part of it is keeping the beer below levels that set off all sorts of staling reactions. Theres no shortage of information on this or much debate really. We know oxygen is bad for beer. The other part, where the argument really lies, is the hot side. Theres published research showing a lot of potential for downstream staling reactions that happen on the hot side. It's not just someones opinion there's real science supporting this.
Now heres the kicker... whether you believe preventing these reactions will allow you to achieve a whole new level of malt flavor is something entirely different and is an opinion people would have to make for themselves. But, I strongly feel its ignorant for people to not read the science for themselves and form your own conclusions.

One last interesting observation worth noting is the claim that most of the commercial beer people drink is already in a phase of changing in character due to oxidation. Stage B is how they word it. Its been proposed that while this is beyond the "factory fresh" or Stage A, people might actually prefer slightly oxidized beer. The example of imports is given and how many people prefer them even though the beer itself is usually well into Stage B or Stage C which is even further into oxidation. The point... while the science shows that these staling reactions are bad for the beer preventing them doesn't always equate towards a beer that people think tastes better.
 
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I think the tone of the paper gets things off on the wrong foot with people, myself being one of those people.

Indeed the tone is awful. It masquerades as science but is an utter failure at the scientific method. He starts with a hypothesis (that minimizing o2 thru the brewing processes will improve flavor), then seemingly devises good procedures to create low o2 beer to test it, then simply declares the idea a winner (all other beer is garbage!), without testing the hypothesis. I'm 100% open to the ideas, but it's still just hypothesis.

It's amazing that so many people are slavishly following the ideas without any idea of the impact.
 
Indeed the tone is awful. It masquerades as science but is an utter failure at the scientific method. He starts with a hypothesis (that minimizing o2 thru the brewing processes will improve flavor), then seemingly devises good procedures to create low o2 beer to test it, then simply declares the idea a winner (all other beer is garbage!), without testing the hypothesis. I'm 100% open to the ideas, but it's still just hypothesis.

It's amazing that so many people are slavishly following the ideas without any idea of the impact.

While I respect what they've done I think the best thing for people to do is remove the PDF authors from the equation. Take a step back and just look at the information thats out there. These guys didn't come up with this hypothesis or these claims, a lot of it is based in the brewing literature they cited. What they did come up with is a way to apply it to the homebrew scale through some creative methods. Granted the way its been put forth comes off as a strong opinion, which some of it is. I don't think people should approach this with the mindset of finding the holy grail, though you could say thats what the authors were after chasing "it". I think the better mindset is, is any of this better for the beer and worth considering in my process?
You can make great beer with some pretty crude methods but it never hurts to evaluate our process and see if we can improve the final product in any way. Don't want to fall victim to the Einstellung effect.
 
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