Daily aeration of wort?

[MarkBowie]

Hi,

The kit I'm fermenting at the minute tells me to "aerate the wort daily". Does that not just increase the risk of infection?

Any advice is brilliant at this point.

 

[chub1]

Hi,

The kit I'm fermenting at the minute tells me to "aerate the wort daily". Does that not just increase the risk of infection?

Any advice is brilliant at this point.

:nono::nono::nono:

 

[Bigjas]

What kit is it? I wouldn't do that. Aerate at the start and then leave it well alone.

 

[MarkBowie]

York brewery Yorkshire terrier. It's a quick mix and ferment kit.

 

[strange-steve]

As soon as fermentation has begun you should avoid aeration. This causes oxidation which leaves a very unpleasant flavour in the brew.

 

[Hoppyland]

I'm all for aeration at the very beginning of fermentation. Oxygen in the wort helps the yeast cells reproduce healthily, so you build up a good crop of active yeast in your beer.
However, if you've pitched a reasonable amount of viable yeast, then this should happen pretty quickly, and a rapid fermentation should result. If it doesn't - and I think this is quite common - then I reckon you'd be better to leave things to take their own time rather than keep aerating (if you're doing it by opening the FV & beating/whisking air into the wort)
After all, if there isn't much yeast activity in an already aerated wort, then I guess there hasn't been much uptake of the oxygen by the yeast. Further intervention might just risk infection.

 

[Fil]

its contrary to the collective wisdom alright. i too would not aerate daily. Yes aerate your wort well prior to pitching, my understanding is similar to whats said above, 02 is a valuable building block for yeast population growth.

once pitched an going leave well alone bar for samples to check the gravity and monitor progress.

If the fermentation stalls consider a rouse (gentle stir to resuspend yeast that may be trapped in food short sediment), But avoid mixing air into the brew. Id also be tempted to email the manufacturer linking in this thread with a polite message along the lines of WTF??
at worst they will ignore you at best you could get a thanks and a free kit or voucher

lets hope the beer is better than the advice given in the instructions..

 

[Cwrw666]

Maybe I'm just being difficult. But I've never ever aerated my wort. Boiling, of course, drives most of the dissolved o2 out of solution, and all I've ever done is pour it straight into the FV, sealed it up and let it cool, then pitched the yeast and got a good fermentation.
Has anyone ever 1) checked whether aeration has ever had any effect, and 2) measured O2 levels in the wort before and after so called `aeration'. It just seems to me to be one more route for getting an infection into your beer.

 

[Simonh82]

Whist I agree that generally there is no reason to aerate the wort after the beginning of the process there are a couple of occasions where it might be suitable.

One is for very high gravity beers. In these situations, it can be beneficial to aerate again after 24 hours to support yeast growth in what can be a pretty hostile environment.

The other is for some highly flocculent strains of yeast which clump together to form a huge krausen on top of the beer. In How to brew British real ale Graham Wheeler suggests these 'northern' strains were associated with the use of Yorkshire square fermentors. This style of fermentor sprayed the fermenting wort over the yeast head to aerate it and help expose the wort to the yeast, which otherwise sits on top of the beer. You can see a description here . On a homebrew scale, these strains can apparently benefit from rousing during fermentation. I think this is borne out by the experience on the Shepards Neame 1698 thread in the yeast forum.

Saying all of that, I would follow the advice above and avoid touching it for at least a week. Generally if a decent amount of healthy yeast is pitched into aerated wort it should complete the fermentation without further intervention.

 

[strange-steve]

Maybe I'm just being difficult. But I've never ever aerated my wort. Boiling, of course, drives most of the dissolved o2 out of solution, and all I've ever done is pour it straight into the FV, sealed it up and let it cool, then pitched the yeast and got a good fermentation.
Has anyone ever 1) checked whether aeration has ever had any effect, and 2) measured O2 levels in the wort before and after so called `aeration'. It just seems to me to be one more route for getting an infection into your beer.

I do agree that aeration isn't as big of a concern as we're often told. I don't think pure O2 injectors are really necessary, especially if using dry yeast or a proper pitch rate. The drop from kettle to FV probably adds enough oxygen, it's all I ever do. Have a look at Brulosophy, they've done a few tests on this and it makes for interesting reading.

 

[MarkBowie]

Thanks everyone. That is what I've read everywhere and seen on here before. Just found myself double guessing as it said on a 'Brewery' kit.

 

[IainM]

Maybe I'm just being difficult. But I've never ever aerated my wort. Boiling, of course, drives most of the dissolved o2 out of solution, and all I've ever done is pour it straight into the FV, sealed it up and let it cool, then pitched the yeast and got a good fermentation.
Has anyone ever 1) checked whether aeration has ever had any effect, and 2) measured O2 levels in the wort before and after so called `aeration'. It just seems to me to be one more route for getting an infection into your beer.

You might find this interesting, at about 13 minutes in:

[ame]https://www.youtube.com/watch?v=2vELwUsBmWQ[/ame]

Of course, she is using a high gravity beer.

 

[terrym]

On a homebrew scale, these strains can apparently benefit from rousing during fermentation. I think this is borne out by the experience on the Shepards Neame 1698 thread in the yeast forum.

Rousing agreed but not with aeration.

 

[Fil]

You might find this interesting, at about 13 minutes in:


Of course, she is using a high gravity beer.

take white labs vids with a pinch of salt, ive watched many when they refer to an initial foam up with the initial boil as all dissolved gasses are expelled as 'The Hot Break' and we all know the hot break takes place after a minimum of 30 minuets boiling and often a lot longer hence the 90 minute boil period for many recipes :whistle:

 

[TheRedDarren]

take white labs vids with a pinch of salt, ive watched many when they refer to an initial foam up with the initial boil as all dissolved gasses are expelled as 'The Hot Break' and we all know the hot break takes place after a minimum of 30 minuets boiling and often a lot longer hence the 90 minute boil period for many recipes :whistle:

I can't be sure I agree there mate, I've watched hot break occur after only a few minutes. In my old kettle the 'egg drop soup' tended to happen only a few minutes in - like less than five.
I rarely boil for more than 70 minutes with pale ales these days and both hot and cold break look pretty strong.

I'm interested to know where you found out that it only occurs after 30 minutes?

 

[IainM]

take white labs vids with a pinch of salt, ive watched many when they refer to an initial foam up with the initial boil as all dissolved gasses are expelled as 'The Hot Break' and we all know the hot break takes place after a minimum of 30 minuets boiling and often a lot longer hence the 90 minute boil period for many recipes :whistle:

I didn't know that. John Palmer says the hot break takes between 5 and 20 minutes, and elsewhere I've read that minimum boil time should be 15 minutes to ensure that the hot break has happened, and I have to say that a short hot break agrees with what I know about protein denaturation and aggregation.

 

[Fil]

my only clue was watching it occur in a small sample prepared for slants and plates..
about 35 minutes into the simmer (beaker was capped with foil) the was clear liquid went all this

 

[strange-steve]

I'm with Fil on this one, I've never seen the hot break in under 30 mins of boiling. What Palmer refers to as the hot break in HTB isn't actually the hot break, this was another of the famous errors in the online version.

 

[TheRedDarren]

Strange. I get that (picture posted by Fil) in just a few minutes! I wonder what the other factors involved are.

 

[TheRedDarren]

Ah, I wonder if 'simmer' is the key word here. It might be about boil intensity.