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Purging fermenter after adding wort?

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Bdogg

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Do you guys purge the oxygen out of your fermenter immediately after first adding the wort?

I oxygenate, pitch the yeast and then got to thinking, should I leave the oxygen in the head for a bit or should I be blowing it straight off?

Using a fermzilla.
 

kadmium

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I wouldn't be purging the oxygen, no. What harm will it do? You just pumped pure oxygen through the wort and now worrying about purging the headspace? I don't really see it as an issue, but I could be wrong.
 
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Do you guys purge the oxygen out of your fermenter immediately after first adding the wort?

I oxygenate, pitch the yeast and then got to thinking, should I leave the oxygen in the head for a bit or should I be blowing it straight off?

Using a fermzilla.
Depends on the yeast you are using. Dry yeast, don't oxygenate the wort, the head space will contain oxygen but hopefully will be forced out during the fermentation by the exiting CO2.
It is nigh impossible to eliminate oxygen from your process, starting from the mash, we do try our best to keep the levels low, even the LODO brewers can't completely eliminate it.
 

Bdogg

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I wouldn't be purging the oxygen, no. What harm will it do? You just pumped pure oxygen through the wort and now worrying about purging the headspace? I don't really see it as an issue, but I could be wrong.
I tend to agree, you know what it's like we go to a lot of effort to avoid oxygenation I figured maybe that half day or so sitting under oxygen might affect it. Thanks for your reply. I won't worry about.
 

Bdogg

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Depends on the yeast you are using. Dry yeast, don't oxygenate the wort, the head space will contain oxygen but hopefully will be forced out during the fermentation by the exiting CO2.
It is nigh impossible to eliminate oxygen from your process, starting from the mash, we do try our best to keep the levels low, even the LODO brewers can't completely eliminate it.
That's interesting, can you expand a bit more on not oxygenating the wort for dry yeast?

I use dry yeast most of the time.
 
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That's interesting, can you expand a bit more on not oxygenating the wort for dry yeast?

I use dry yeast most of the time.
Dry yeast comes with all it's sterols and everything else it needs in a little back pack. It has no need of any oxygen. The yeast goes straight into anaerobic fermentation. It was discussed last week on another thread, whichever yeast you are using read their PDF of how to use it, if it is a MJ yeast they may not have changed the wording on their website but being as their yeasts are other yeasts re badged they fall into the same category.
Tori (Mangrove Jack's)

Sep 17, 2020, 6:30 GMT+1

Hello,

Our yeast is ready to go from the moment you open the packet, no need to oxengenate it.
 

Bdogg

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Thats super interesting man, thanks for the input.

Are liquid yeasts different?
 

MHB

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Dry yeasts are harvested at a time in the life cycle of the yeast where it has built up its reserves of everything it needs to reproduce and then ferment the wort, so there is no need to add Oxygen and any that is in the wort or head space will be consumed fairly quickly.
There is one big caveat! If you use enough yeast. If you under pitch the yeast will need to reproduce more to reach an effective population, for that it will need O2 among other things.
To not need oxygen follow the instructions for commercial pitches, using US-05 as an example, look at the info sheet which says 50-80g/hL, 1 of 11.5g satchel in 23L is 50g/hL so right at the bottom of the range and would be enough for a light (say<1.045) beer but not enough for a big beer like a 6-7% IPA.

One other point is that I find beers that are well pitched into an Oxygenated wort taste better, so I'm going to keep oxygenating, pitching at the higher end of the range, controlling the temperature, get off the trub before two weeks are up...
Mark
 

Bdogg

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Dry yeasts are harvested at a time in the life cycle of the yeast where it has built up its reserves of everything it needs to reproduce and then ferment the wort, so there is no need to add Oxygen and any that is in the wort or head space will be consumed fairly quickly...
Great info, thanks a lot. I know it's off topic but going on from what you said about getting off the trub before two weeks, is there any benefit to getting rid of the trub earlier?
 

MHB

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Get of the trub as soon as you reach FG.
After 2 weeks the oldest yeast will (not might) start the processes that end up in autolysis. One of the first things that happens is the old yeast starts to release Protease-A, its odorless and flavourless but it will start chopping up the proteins that build head, enough of it and it will start disordering yeast cell walls and then your beer will be truly stuffed.
All the textbooks on brewing say that after 2 weeks there is measurable harm to the beer, if you haven't reached FG in 7 days you have underpitched or are brewing at the wrong temperature (mostly & a few other causes). So to make the best beer, brew for as little time as you can and get the beer into package asap.
Mark
 

kadmium

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Yes, and as a side note dry yeast don't go straight into anaerobic fermentation, they simply have enough reserves to do a healthy division for a few generations. The only way they would go straight into fermentation is if you pitched a huge volume and they didn't need to reproduce first.

I've found that 1 packet with proper oxygenation definitely starts off sooner than 1 pack that isn't. I know the big yeast guys say it's not necessary but that's exactly as MHB described, if you're pitching enough. Which is probably 2 packs for a standard ale, and 4 or 5 for a lager. Might as well buy liquid and do a starter for that price!
 

Bdogg

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Get of the trub as soon as you reach FG ...
That's amazing info Mark, it's right at the edge of where I am with brewing knowledge and I'll put it straight into practice.

I really appreciate it, you've changed my techniques, honestly that's gold. Thanks a lot.
 
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That's interesting, can you expand a bit more on not oxygenating the wort for dry yeast?

I use dry yeast most of the time.
Always good to do a bit of your own research, a worthwhile read is Tracy Aquilla's the role of oxygen in fermentation. Doesn't matter who's dried yeast you use they are all pretty much the same MO.
 

scomet

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No need, DO is only an issue post fermentation / packaging, plus if you’r using a closed fermenter the 02 will be blown off fast, too much BS is talked about oxygen, not referring to you, good question btw.

scomet
Open-fermentation-for-its-weizens-at-Ayinger..jpg
 

yankinoz

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the head space will contain oxygen but hopefully will be forced out during the fermentation by the exiting CO2.

The volume of C02 is many times greater than typical headspace volume, a calculation I've posted on a different thread. C02 comes in at the bottom and pushes air out the top. Although C02 is a bit heavier than air, there is presumably some back diffusion of 02, but since a krausen is in the way, that is presumably vanishingly small. So by the time the krausen drops, oxygen should be absent or close to it, unless the fermenter leaks.
It is nigh impossible to eliminate oxygen from your process, starting from the mash, we do try our best to keep the levels low, even the LODO brewers can't completely eliminate it.

I brew here:
 

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