Aeration

[Jus]

Hi All

I was wondering if anyone could tell me a little bit about Aeration.

I understand that you should Aerate before pitching your yeast but i dont really understand:
1. Why this needs to be done
2. What are common methods of Aerating?

Cheers!
Jus

[Kevnlis]

Aeration must be done to help the yeast to grow in numbers. The most common method of aeration is simple pouring of the wort (or water to be mixed with the kit and kilo) into the fermentor.

Have a read of Palmers section on yeast:

http://www.howtobrew.com/section1/chapter6.html

[warra48]

Remember, there is no need to aerate the wort if you dump a brew onto a yeast cake, as the yeast are already conditioned to working anaerobically.
For liquid yeasts you do need to aerate your cooled wort before pitching.
There seem to be arguments for and against on whether it's necessary for dried yeast. Any expert brewers wish to comment on this?

[Jus]

So it aerates as it passes through the air? or as it churns when it hits the fermentor?

[Chris]

Jus, I am going to assume that you are just brewing kits at the moment? Let me know if this is incorrect.

Ok, you add your malt (kit and other sugars) to your fermenter with the boiled water, then add cold water to top it up to 23L or whatever volume you use. If you (like me at a similar stage) add the water to the fermenter via the good old garden hose, then you are already adding enough oxygen to the wort. That on top of the fact that dried yeast (like in kits) doesn't really need O2. It is still good practice to aerate though.

The main reason for aeration of the wort is to give the yeast the O2 it requires for its reproductive phase- where it ups its numbers to the levels it needs to ferment out the beer.

Once this phase is complete, it then no longer needs O2, and aerating the beer will impact negatively on the beer.

[Chris]

And in relation to your last post, the wort aerates as it "churns" around in the bottom of the fermenter.

[lethaldog]

If you have a strainer then pour through it into the fermenter, this has always worked well for me

[Trough Lolly]

When I boiled using two stock pots, I used to grab a clean 1L jug and aerate the chilled wort by scooping up wort and splash pouring it back into the stock pot for a few minutes for each pot - then a splash pour through a strainer as Lethal suggests and you've got a fermenter with well aerated wort ready for yeast innoculation...

Cheers,
TL

[ryan]

and don`t forget- never aerate your wort when it is above 26*. {but we did that one last week }

[Trough Lolly]

...hang on a sec! I better check Palmer on that one...

[ryan]

Ever used Mt. Hood hops, Trough?

[Jus]

Chris, yes i am brewing kits at the moment.

Thanks everyone, you've given me the answers i needed

Cheers
Jus

[Rod]

I use a paint stirrer , the sort like a plunger

good aeration and the yeast seem to start better

[Trough Lolly]

Ever used Mt. Hood hops, Trough?

Yes, once, a couple of years ago, when I did an experimental "Fat Tire" clonebrew - I can't recall the exact flavour profile but I do remember that the beer tasted pretty good...

Mt. Hood (USA)
This cultivar was the result of a cross made in 1983 between a colchicines iinduced tetraploid female Hallertau Mittelfruh (USDA 21397) and a male hop (USDA 19058 M). In 1985, the number USDA 21455 was assigned for Mt. Hood. It is a high yielding, early to mid-season ripening hop with oil contents very similar (hence, also a similar aroma) to that of Hallertau Hersbrucker.
It is fairly resistant to Downy Mildew, hence suitable for growing in Oregon and Idaho, but it is also cultivated in Washington State. It is
sensitive to Wilt. The alpha acid ranges from 4.0-6.5%, with beta acid ranging from 3.6-5.9%. It is, in my opinion, very suitable for use in ales as well as lagers.

[ryan]

In a moment of madness, I combined Mt. Hood with T58 yeast and dry hopped with Cascade, bit of an experiment ale. I was underwhelmed with the result. Almost has a slight lactic tang. that would be the T58, I`m guessing

[Trough Lolly]

Hmmmm, T-58 and Cascade - that can be an interesting combo!!

Cheers,
TL