# Hot Side Aeration



## Goose (15/1/07)

G'day lads,

Either the search engine is too stupid or I am (ok ok) but struggling to find something comprehensive on the topic. Been trying to read up on this a bit more but as usual I come to some conflicting views...

Palmer says HSA can occur to the wort at any temperature above 80F (27 deg C). So that means that one has to minimise splashing etc when transferring wort from the mash tun to the boiler. Fair enough. Further reading however suggests that HSA effects can be prevalent due to oxidation of enzymes. That means if they are denatured "properly" in a mashout then HSA should not be a problem. 

From a yankee forum:


> I just read in Papazian's Complete Joy that hot side oxydation is caused by the oxydation of enzymes. Once the enzymes are deactivated at 170 degrees, hot side oxydation isn't an issue.



Comments welcome please.... because when I transfer my wort from the mash tun I have been pouring it through a strainer... have no choice but to splash it into my boiler... :blink: is this bad, even though I do a 75 deg C mashout ? 


Goose.


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## tangent (15/1/07)

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

have a listen to this - don't panic, have a homebrew


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## Keifer (15/1/07)

Personally i don't know whether it's true or not, so i minimise the amount of splashing i do (except into the fermentor). In my simple 3 tier AG system the only times HSA may occur would be stirring & recirculating the mash, and then when x-fering from mash tun to kettle. So i just take it nice and easy in those 3 areas of brew day. Easy as!


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## Screwtop (15/1/07)

Use a pinch of Sodium Met in the mash and relax!


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## Finite (15/1/07)

Screwtop said:


> Use a pinch of Sodium Met in the mash and relax!



whats the idea here screwtop?


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## Goose (16/1/07)

Hey Tangent, thats an excellent and informative listen, top man thanks.

In summary, HSA risks appear to be prevalent mainly in the dough in phase of the mash, not post mash or post boil. Mr Palmer, in a cameo appearance describes it well.

Finite, Screwtop is coming from something mentioned in this broadcast, apparently a sodium met tablet in the mash can help to bind/remove any oxygen in the mash that can cause the oxidation that can cause problems later .... have a listen.

Goose



edit for sp


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## PostModern (16/1/07)

A pinch of sodium met in in the HLT is all you need. It's a powerful anti-oxidant, sucks up any O2 before the lipids can. It also breaks down chloramines if your water contains those. Just a pinch will do it.


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## Airgead (17/1/07)

PostModern said:


> A pinch of sodium met in in the HLT is all you need. It's a powerful anti-oxidant, sucks up any O2 before the lipids can. It also breaks down chloramines if your water contains those. Just a pinch will do it.



Folks

Does anyone know of any alternatives to Sodium Met? That stuff can do nasty things to the airways and with an athsmatic wife in the house I'm reluctant to use it. I suppose any food grade antioxidant that didn't add flavour would do. Anyone had any experience with anything else?

Dave


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## JasonY (17/1/07)

The amount you are adding is literaly a pinch, you should not even smell it if that helps?


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## Keifer (17/1/07)

Is that stuff safe to drink? whats in it chemically?


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## Adamt (17/1/07)

Sodium met = Sodium Metabisulphite Na2 S2 O5

It is used to remove chloramine and oxygen from water, SO2 is evolved on contact with water. 

You can look at is as another salt that adjusts the water profile. A pinch in a batch will not cause any problems.


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## JasonY (17/1/07)

Apprentice_Brewer said:


> Is that stuff safe to drink? whats in it chemically?



No expert but it is used in a lot of stuff from wine to foods so within reason I am sure it is not a problem but stirring it into your cup of coffee in the mornings is probably not advisable 

http://en.wikipedia.org/wiki/Sodium_metabisulfite


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## tangent (17/1/07)

check out Charlie Papazian's addition - cinnamon. 1/2 tsp in the mash. it sucks up the O2 as well and in the small amount you can't taste it

it's all in Basic Brewing if you care to do some research.


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## sam (17/1/07)

Dave,

Another option is ascorbic acid, it should stop potential oxidation in the mash.

It's used sometimes in winemaking. I think it might have a bit of a taste, not sure about quantity used.

I had a quick googley, some HBer people use it in the mash it seems. Also used as a bottling preservative.

Anyway, I think it's less irritating than pot met.

sam


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## Airgead (17/1/07)

Thanks folks

Its not so much the pinch ion the mash that woul dbe the problem its the bag of it sitting around that may cause problems if it wasn't sealed properly of if the missus wandered past when I had it open. A trip to the hospital would probably ruin the brew more than a little HSA.

I might give the ascorbic acid a try. Shouldn't need much so taste should be fine.

Cheers
Dave


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## hefevice (17/1/07)

tangent said:


> check out Charlie Papazian's addition - cinnamon. 1/2 tsp in the mash. it sucks up the O2 as well and in the small amount you can't taste it



What I like about [sodium|potassium] met is that it will take Chloramine out of the water as well as acting as an antioxidant for the mash. Any idea what (if any) effect cinnamon may have on chloramines?


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## Adamt (17/1/07)

Wikipedia suggests it is a good antioxidant, and has antimicrobial properties, but no mention of chloramine, and I would guess that it would have no effect whatsoever on chloramine.


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## PostModern (17/1/07)

I doubt cinnamon would break down chloramines.  But you never know.

I keep my met in a sealed plastic tub. I'm sensitive to it too, but I'm not asthmatic, so I have no issues handling it. I literally take a pinch out of the tub with dry fingers and sprinkle into the tun. I then wash my hands, never had an issue. It's also a handy antimicrobial cleaning agent for washing out the mashtun, etc. I wear gloves when doing that.


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## Screwtop (17/1/07)

sam said:


> Dave,
> 
> Another option is ascorbic acid, it should stop potential oxidation in the mash.
> 
> ...



Ascorbic acid (Vitamin C) is used in the brewing industry and in particular the baking industry to speed up and improve fermentation.
Cheers.


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## tangent (17/1/07)

no chloramines in my water so cinnamon is cool
clove is s'posed to be heaps more powerful but i reckon you'd get the smell come through. Might be the go around your missus though Airgead.
http://www.phytochemicals.info/research/an...dants-herbs.php


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## bonj (17/1/07)

You need a fair amount of air turbulence to make it airborne. I'm asthmatic, and with precautions, I have never had a problem with it.


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## Finite (17/1/07)

So if I add a pinch of sodium met to my mash then I dont have to worry about splashing and airating my hot wort?


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## MHB (17/1/07)

I think you have to worry about everything all the time when brewing, if you work at it you could add enough oxygen to overcome the benefit from any anti-oxidant.
If a "pinch" is enough, for someone taking care, that doesn't mean its enough no matter what you do.

Re ascorbic acid, if memory serves its quite sensitive to heat, I can't see it making it into the kettle, defiantly wont be making it out - unchanged, it may be of some benefit in the water at the start but I would need to be convinced. The amount required to act as an oxygen absorber would I think be noticeable in the flavour of the finished beer (well its breakdown products).

Similar concerns about Sodium Met, I can't see a pinch being a magic bullet. Good brewing practice should be enough to prevent problems from HSA, if you are really worried, de-air/chlorinate your water by boiling and set your system up so everything is underlet and you won't any have any problems.

We have yeast on our side, HAS is really a problem for the long term stability of filtered pasteurised, packaged commercial beer. Because we have one of natures best little O2 absorbers in our beer this isnt a real concern.
In fairness it might be important to those who NO-CHILL (ducking) too much O2 will harm a stored wort, and I would be exercising all care to reduce O2.

Anyone got a good link to how the chemistry of SO2 is supposed to work?

MHB


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## Kai (17/1/07)

MHB said:


> Re ascorbic acid, if memory serves its quite sensitive to heat, I can't see it making it into the kettle, defiantly wont be making it out - unchanged, it may be of some benefit in the water at the start but I would need to be convinced. The amount required to act as an oxygen absorber would I think be noticeable in the flavour of the finished beer (well its breakdown products).



I was going to post something quite similar to this. Ascorbic is not a strong anti-oxidant. In fact, in bread its role is that of an oxidising agent if memory serves correctly. I would not count on it doing anything in the mash at all.


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## Screwtop (17/1/07)

Kai said:


> I was going to post something quite similar to this. Ascorbic is not a strong anti-oxidant. In fact, in bread its role is that of an oxidising agent if memory serves correctly. I would not count on it doing anything in the mash at all.



Off topic but for interest sake: There are heaps of references to the use of ascorbic acid in baking, can't see it being useful in the mash, but it can be used to aid all fermentation, did a quick search and found this reference "The ascorbic acid (Vitamin C) and diastatic malt act as yeast activators which insure that your yeast yields the maximum rise" Link Here. In baking, products incorporating ascorbic acid are known as Instant Bread Improvers, for the fermentation speed achieved with their use.


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## Kai (18/1/07)

Yes, it's important in baking. Dough formation involves reduction and oxidation reactions and ascorbic acid provides the oxidation reactions required. I believe it's commonly used in place of potassium bromate which I think is not considered a nice chemical.


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## Thirsty Boy (18/1/07)

Mega Brewers add a little ascorbic acid to thier beer at roughly the point where they Filter / Thin down the high gravity beer to sale strength.

But then again, its only a little bit, and their brewing practises are so much more able to exclude O2 than ours that they are barely comparable, so I'm not sure how relevant it is to this discussion. Just general info I suppose.


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## Kai (18/1/07)

That's the point where they thin down the beer, that's different to pre-ferment processes.


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## Ross (18/1/07)

I always give my mash a vigorous stir & don't use sodium met or anything else for that matter - Never stressed about HSA & have never experienced it in one of my brews... So until i do, it remains something i personally don't worry about...

Cheers Ross


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## warrenlw63 (18/1/07)

Airgead said:


> Thanks folks
> 
> Its not so much the pinch ion the mash that woul dbe the problem its the bag of it sitting around that may cause problems if it wasn't sealed properly of if the missus wandered past when I had it open. A trip to the hospital would probably ruin the brew more than a little HSA.
> 
> ...



Airgead

Don't really need to worry about a bag of it sitting around. Just buy some Campden tablets which are the same thing (in tablet form duh!). No aromas until you crush. I usually break off around a quarter of one per 42 litre brew, crush it and add to the mash. Even if you break a bit of a tab it still doesn't seem to give off any sulphur aromas until you crush.

I've been doing this for around 18 months. Beers never seem to stale... OTOH could well be a placebo because my beers weren't staling previously. :blink: 

Warren -


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## /// (18/1/07)

HSA is a downstream issue, partcuarly as MHB has mentioned with pasturised beer.

For the HB perspective i would not worry about it, having asked one of the highest trained and expereinced brewers (recently retired) he echoed these words. If you have ever seen a grant run or a whirlpool then you'll never worry again, a grant really gets the wort and air mixed up.

Running a floating mash o2 is important within the percap regions of the crushed grain to hold the grain up in the mash - aka to help float. A courser grind and a gentle dough-in will ensure very brite worts on the opening of tap (with slow run off) and can be acheived no matter the size of brewing.

I'd worry more about obtaining brite worts than oxidation, by the time most guys have finished there beer at home alot of trade beer is still waiting to go on a shelf.

Crush coarser and run slow is my motto for this year,

Scotty


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## Guest Lurker (18/1/07)

There are a few references to ascorbic acid being good for yeast in the posts above. Off topic a bit, but someone specifically asked Chris White that question in Perth, he had never heard that, and couldnt see any reason why it would be beneficial.


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## Stuster (18/1/07)

MHB said:


> if you are really worried, de-air/chlorinate your water by boiling



I agree with you on the low risk of HSA in a homebrewing setup, but chloramines will not be removed by boiling. According to this water utility site



> Chlorine and chloramine must be removed from the water .... There are two ways to remove these disinfectants:
> 
> * Adding ascorbic acid, or
> * Using a granular activated carbon treatment.



So that may be why mega breweries add ascorbic acid. I think I'll stick with my water filter. Another read on this here. Sorry to get OT but it seems like the topics are related.


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## devo (18/1/07)

Goose said:


> G'day lads,
> 
> Either the search engine is too stupid or I am (ok ok) but struggling to find something comprehensive on the topic. Been trying to read up on this a bit more but as usual I come to some conflicting views...
> 
> ...



I think an important question to ask is, has anyone actually ever tasted the effects or know what taste it imparts to the brew? I don't actually think anyone does?


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## Finite (18/1/07)

Ross said:


> I always give my mash a vigorous stir & don't use sodium met or anything else for that matter - Never stressed about HSA & have never experienced it in one of my brews... So until i do, it remains something i personally don't worry about...
> 
> Cheers Ross



I tend to agree ross,

After listerning the the basic brewing HSA experiment show they could detect MINOR subtleties but even john palmer said "if this was a blind taste we wouldnt notice any difference".

And these brews where actually aerated after the mash and boil. In not going to go splashing my hot wort around but untill I notice a definate defect from it im not going to go out of my way to avoid a couple of bubbles.


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