Improving Wort Aeration

[danwlx]

Hi guys,

I’m planning on brewing a lager shortly and my past efforts have been good but not great. I’ve been reassessing all my brewing processes recently and have made a number of changes in an attempt to improve results, I’m now kegging in cornies, I have a fermentation fridge and I’m treating my water in an attempt to get the correct mash PH (although I don’t have a meter to test his and I have never got on with strips).

One area that I’m looking at improving is wort aeration. At the moment I drop wort (from height) from the boiler to a plastic bucket with tap to splash as and introduce O2, I then transfer from this bucket again from height into the FV, so 2 splashy transfers to introduce O2.

For the lager I am considering upping this to 4 or 5 transfers however in your experience:

- Is this required / does this improve the O2 saturation in the wort?
- Does this method present a high risk of contaminating the wort with airborne
nasties?

Having spent plenty recently on improving my set-up, any O2 injection equipment is a no-go at the moment so I am limited to more basic methods at present!

Cheers
Dan

[rpt]

What type of yeast are you going to use? If it's dry then aeration is not needed.

[danwlx]

Hi Rpt, surely all yeast, whether dry or liquid, needs dissolved O2 in the wort to consume during early fermentation?

[jonny-x]

There's a good episode of basic brewing radio from Aug7-2008 that made sense to me.

http://media.libsyn.com/media/basicbrew ... ration.mp3

My take from it is shaking/rocking the fermenter is as good a way of aerating the wort as any (assuming you're brewing small enough batches to be able to rock the fermenter) and it minimises exposure to possible infection.

[DeadFall]

I haven't tried it myself yet, but venturi tubes are meant to be good. I'll be giving this a crack on me next brew.

[Piscator]

Hi Rpt, surely all yeast, whether dry or liquid, needs dissolved O2 in the wort to consume during early fermentation?

In theory dried yeast has been produced with sufficent reserves for cell wall synthesis (which is when oxygen is needed) making oxygen levels less critical.

You mentioned correcting alkalinity - how are you doing this? Reason for asking is that if you use AMS/CRS you might be putting the sulphate above levels ideal for lager.

Cheers
Steve

[danwlx]

Hi Steve, thanks for the info, I was unaware that dried yeast was more forgiving. Usually I would use phosphoric acid to reduce alkalinity but for this brew am planning on using a low mineral content bottled water (tesco ashbeck).

[Jimmy321]

I make really good lagers and I only use one drop from the boiler to the FV, biggest improvement for me was pitching large volumes of yeast.