Aeration Or Am I On The Wrong Track?

[thanme]

So I recently picked up a 30L Birko that I'll be using for my next brew (Extract). When the boil has fininshed, I know I need to aerate the wort, and I figured a good way to do this was just from the tap on the urn into the fermenter (via a strainer). Apart from being a little higher than where I'd pour from my stock pot, is there a problem with this?? Like, my urn will be on the bench, fermenter on the floor. I'm just wondering if it might be a bit much. I remember reading something about splashing, but I think that's just for racking, but I'd like to double check.
If I need something to attach to the urn tap to move the hot wort, silicon is the go right?

 

[Steve]

So I recently picked up a 30L Birko that I'll be using for my next brew (Extract). When the boil has fininshed, I know I need to aerate the wort, and I figured a good way to do this was just from the tap on the urn into the fermenter (via a strainer). Apart from being a little higher than where I'd pour from my stock pot, is there a problem with this?? Like, my urn will be on the bench, fermenter on the floor. I'm just wondering if it might be a bit much. I remember reading something about splashing, but I think that's just for racking, but I'd like to double check.
If I need something to attach to the urn tap to move the hot wort, silicon is the go right?

If you arent going to chill the wort in the urn get some food grade reinforced tubing from bunnings that will fit the urn tap and slowly get it into the fermenter to chill. Dont pour the hot wort straight from the tap into the fermenter. You only want to aerate it when its cool, before pitching the yeast.
Cheers
Steve

 

[Dave70]

Another method.

http://www.absolutehomebrew.com.au/?page_id=54

This is what I do anyway.

 

[Fourstar]

If you arent going to chill the wort in the urn get some food grade reinforced tubing from bunnings that will fit the urn tap and slowly get it into the fermenter to chill. Dont pour the hot wort straight from the tap into the fermenter. You only want to aerate it when its cool, before pitching the yeast.
Cheers
Steve

And the reson for this, which you forgot to note Steve is OXIDATION. That is unless you want your beer to taste like a wet box... a wet cardboard box.

You could probabaly NC in the urn if you can seal the lid up somehow (e.g. gladwrap it). once its cool, simply sinitise the outlet and let it slash away into the fermenter.

Cheers

 

[thanme]

You only want to aerate it when its cool, before pitching the yeast.

Ok cool. That's what I needed to know

And the reson for this, which you forgot to note Steve is OXIDATION. That is unless you want your beer to taste like a wet box... a wet cardboard box.

I guess I didn't think there was a difference between oxidation and aeration So if I do a full boil, then NC my wort in the fermenter, can I just swirl it around prior to pitching yeast once it's cool enough?? Or am I better off with a cube? Or even saving a few litres of water to add at aeration time?

Truth be told, I'll probably boil/chill half the water beforehand and only do a half boil, but I'd like to do the whole lot purely because I have the space now

 

[avaneyk]

....
You could probabaly NC in the urn if you can seal the lid up somehow (e.g. gladwrap it). once its cool, simply sinitise the outlet and let it slash away into the fermenter.

That pretty much what I do, except I use an immersion chiller in my 50L stock pot and syphon cooled wort into my fermenter with about a 1.5 metre drop from the end of the syphon hose to the bottom of the fermenter. This seems to aerates the wort enough. I get airlock activity within a few hours of pitching my yeast.

 

[avaneyk]

So if I do a full boil, then NC my wort in the fermenter, can I just swirl it around prior to pitching yeast once it's cool enough?? Or am I better off with a cube? Or even saving a few litres of water to add at aeration time?

I think you'll need to do a bit more than swirl it around. At the very least you'll need to beat the wort senseless with a sanitised spoon. I'd do what FourStar recommended cos it'll give you better aeration.

 

[Bribie G]

I 'no chill' in a cube and when it's at pitching temperature I pour from a reasonable height into the fermenter with as much splashing as possible. Some yeasts have higher oxygen requirements than others. Most 'mainstream' yeasts such as US-05 can be sealed up at this point and no problems. However there are some yeasts that need a lot of aeration, for example Ringwood and West Yorkshire 1469. Generally "North English" yeasts like to be thrashed a couple of times a day for the first few days. I use one of these:


On the subject of 'hot side aeration', I would have to say that the HB community is divided on this one. Fourstar is clearly in the 'wet cardboard box' camp. Personally I transfer to the cube from my urn straight from the tap with no tube. I've done over 50 AG brews and no problems. However I have bought some silicone hose and when I get the urn fixed up with a ball valve with a spigot that can take the tube then I'll do it the other way. Then I'll see how the cow sits in the cabbage patch B)

 

[thanme]

Cool cool. All sounds good
I might NC in the urn this time around as it seems easiest Plus I don't have a cube yet

While on the topic of cubes (although not directly related), how long could you potentially keep non-fermented wort in a cube? Say I had more time to do a brew a few days before my fermenter freed up. Would to be ok to keep in the cube, in the fridge?

Dave: That article was really interesting!

 

[avaneyk]

BribeG,
when you refer to Northern English style yeasts, is that mainly the liquid varieties? I pitched (rehydrated) dry Nottingham (forgive my ignorance of English geography is this isn't from the north...) on wednesday with the aeration being only splashing the wort into my fermenter. It started firing within 5hrs. Normally I'd just let ferment at this point. Should I be aerating this type of yeast more over the first few days or is what I'm doing ok?

Cheers,
Andrew.

 

[Sammus]

And the reson for this, which you forgot to note Steve is OXIDATION. That is unless you want your beer to taste like a wet box... a wet cardboard box.

You could probabaly NC in the urn if you can seal the lid up somehow (e.g. gladwrap it). once its cool, simply sinitise the outlet and let it slash away into the fermenter.

Cheers

I think you're getting mixed up. The reason is HSA (hot side aeration) which arguably makes no difference anyway. wet cardboard oxidation is aerating/oxidizing post fermentation.

Either way, it's preferably not to splash it around much when it's hot, but shake the sh!t out of it when its cool

 

[tdh]

N.B. No need to aerate if using dried yeast (used first time from the packet, if re-pitching then aerate just like a liquid yeast)

Just don't splash (aerate) if hot or post-fermentation.

tdh

 

[avaneyk]

N.B. No need to aerate if using dried yeast (used first time from the packet, if re-pitching then aerate just like a liquid yeast)

Just don't splash (aerate) if hot or post-fermentation.

tdh

Can you explain this further? I realise that dried yeast has glucose stored within the cells before its dried but the directions on the pack say to ensure aeration.

Andrew

 

[tdh]

Glycogen, not glucose.

Which pack?

tdh

 

[avaneyk]

Glycogen, not glucose.

Which pack?

tdh

I don't have one in the fridge at the moment, but from memory both the SAF and Danstar yeasts I've used say to aerate the wort well before pitching.

 

[technocat]

Fourstar is clearly in the 'wet cardboard box' camp.

And he is dead right. HSA leads to oxygenating hot wort and will give an off flavour such as wet cardboard.
It doesn't happen post fermentation and is the reason for a submersible sparge device.

 

[Bribie G]

Generally, the dried yeasts such as Nottingham are good to go straight away, as long as they are pitched into well aerated wort. With kit and partials brewers this is not usually an issue because there will be a fair amount of tap water going into the fermenter which is nicely aerated anyway.

However with AG worts where the whole volume has been boiled, it's desirable to have a good amount of oxygen in the brew; splashing and rousing usually does a good enough job. Some people use fish tank aerating stones, I haven't used that method. As long as you get a good splash into the fermenter I reckon that's going to be good enough. Extra rousing and aerating is only beneficial for a few top fermenting yeasts such as West Yorkshire etc that were specifically bred for the Yorkshire Stone Square system and were (are, in the case of existing breweries such as Sam Smith) roused frequently.

Goody here's a chance to post that picture again

 

[avaneyk]

Generally, the dried yeasts such as Nottingham are good to go straight away, as long as they are pitched into well aerated wort. With kit and partials brewers this is not usually an issue because there will be a fair amount of tap water going into the fermenter which is nicely aerated anyway.

However with AG worts where the whole volume has been boiled, it's desirable to have a good amount of oxygen in the brew; splashing and rousing usually does a good enough job. Some people use fish tank aerating stones, I haven't used that method. As long as you get a good splash into the fermenter I reckon that's going to be good enough. Extra rousing and aerating is only beneficial for a few top fermenting yeasts such as West Yorkshire etc that were specifically bred for the Yorkshire Stone Square system and were (are, in the case of existing breweries such as Sam Smith) roused frequently.

Goody here's a chance to post that picture again

View attachment 31314

Cheers,
so it sounds like I've been doing the right thing - aerating by splashing cooled wort into the fermenter. I haven't moved to liquid yeasts yet. Will do that when I've got a few more AG's under my belt.

Andrew

 

[Sammus]

Yeah upon reading we're both right. HSA can theoretically release oxygen later staling the beer, much like introducing oxygen post fermentation. However, evidence for HSA on a homebrew scale is almost nonexistent, but a lot of us probably have first hand experience with post fermentation aeration problem.

 

[tdh]

from the Fermentis US-05 fact sheet -

Re-hydrate the dry yeast into yeast cream in a stirred vessel prior to pitching. Sprinkle the dry
yeast in 10 times its own weight of sterile water or wort at 27C 3C (80F 6F). Once the
expected weight of dry yeast is reconstituted into cream by this method (this takes about 15 to
30 minutes), maintain a gentle stirring for another 30 minutes. Then pitch the resultant cream
into the fermentation vessel.
Alternatively, pitch dry yeast directly in the fermentation vessel providing the temperature of
the wort is above 20C (68F). Progressively sprinkle the dry yeast into the wort ensuring the
yeast covers all the surface of wort available in order to avoid clumps. Leave for 30 minutes
and then mix the wort e.g. using aeration.

and from Dr. Nathan Cone (Lallemand)
http://www.danstaryeast.com/library/aeration_vs_wort.html

>I don't have one in the fridge at the moment, but from memory both the SAF and Danstar yeasts I've used say to aerate the wort well before pitching<