Wort Aeration Device

[puffer555]

Hi Guys,

I have thinking of a better way to aerate my wort at the end of the brew.
I currently use a ceramic aquarium air stone, sanitary filter and air pump (like a lot of people).
While it works, I am not totally happy with it as I can see potential for infection (lots of places for bugs to hide).
It also adds extra time to the brew day, and requires more peripheral equipment (which i already have, but I like to tinker anyway).
I dont want to go down the route of compressed O2, however I like the idea of a more permanent stainless air stone connected straight to the chiller.

Anyway, I have been researching other options, and came across this thread on a simple venturi aerator that a lot of guys in the states are using with great effect.
http://www.homebrewtalk.com/f51/cheap-easy...n-gadget-68218/

While I could use the same design, I wasn't happy with the fact that unfiltered air is being sucked into the wort.
It got me thinking about a way to filter the air, and also a way to make the components more hardwired.
Anyway, I have come up with the following idea.


It utilises camlock fittings which I already have on all my equipment/hoses.
This just fits between the male camlock on my kettle and the female camlock on my hoses.
The venturi is just some beer hose that has been cut on an angle (positioned downstream of the flow).
The increased velocity and wake created around the tube creates a low pressure zone which draws in the air (venturi action).
I have used this venturi design before on my saltwater aquarium with good results.

Anyway, It can be connected to my kettle at the end of the boil.
It can then be heat sterilised by recirculating through it (with air tap closed to eliminate HSA).
Once the wort is chilled (I chill in my kettle - whirlpool immersion chiller), the airtap is opened.
I can then either continue to recirculate and aerate in the kettle, or while transferring to fermenter.
All wort will pass by the venturi and should have some contact with the filtered air = good aeration.

Anyway, I already have a lot of the fittings required.
It is similar in principle to the US design but more sanitary (easier to clean also).
I also like the fact that it is more permanent.

Anyway, Let me know your thoughts.

Cheers
Tim

 

[grimpanda]

From a brewers perspective with little scientific or engineering background this looks like a great solution. I actually have all of the equipment needed for pressurized O2 aeration but haven't yet used it due to the inconvenience of the extra steps in setting up, sanitising etc.

If you do go ahead and put one together you should do a side-by-side test against other aeration methods and get the wort checked for DO levels.

Gabe

 

[puffer555]

From a brewers perspective with little scientific or engineering background this looks like a great solution. I actually have all of the equipment needed for pressurized O2 aeration but haven't yet used it due to the inconvenience of the extra steps in setting up, sanitising etc.

If you do go ahead and put one together you should do a side-by-side test against other aeration methods and get the wort checked for DO levels.

Gabe

Might be a good experiment.
Nowhere near that of O2 though.
As long as its as good or better than my current method.

 

[roller997]

A much simpler solution is to get yourself a wine aerator which works on the venturi principle.
I bought a few for $29.95 some time ago from an online shop. The idea for wine is that it is equivalent to having the wine in a decanter for more than an hour.
I think the ones I have here are cheap knock offs but their construction is so simple - I just treat it with some sanitizer before I pour the chilled wort through the venturi unit. You can hear it suck the air in and the bubbles on the fermenter suggest there is a bit of turbulence being created.
Here is the original venturi website
http://www.vinturi.com/
The units I have look identical and I have been using them as presents for family as they are hard to find. (Correction, typing in Vinturi on ebay yields plenty of results).

Regards

Roller

 

[puffer555]

Looks interesting but the air is not filtered.
Might be easier to just use the racking cane with a few holes.

 

[roller997]

I suspect you might not be quite on the mark with your response.

I haven't seen too many commercial breweries where the air inside their fermenter is filtered but then I have only been to three so far.
I don't believe there is much risk of an airborne infection since there are many commercial breweries who have open fermentation vessels for different ales & wheat beers. In the past most of the wheat beers used to be open fermented and White Rabbit do it now for their ales, indicating that airborne infections are not a great concern for them.

I would expect there is much greater chance of infection from your camlock fittings if they haven't been cleaned properly than through the surrounding air not being filtered.

In terms of simply drilling holes in a racking cane - that doesn't really introduce the air - Makes the wort go all over the place but it isn't really making use of the venturi principle to suck air in.

Keep us posted on how you go.


Cheers

Roland

 

[kevin_smevin]

I suspect you might not be quite on the mark with your response.

I haven't seen too many commercial breweries where the air inside their fermenter is filtered but then I have only been to three so far.
I don't believe there is much risk of an airborne infection since there are many commercial breweries who have open fermentation vessels for different ales & wheat beers. In the past most of the wheat beers used to be open fermented and White Rabbit do it now for their ales, indicating that airborne infections are not a great concern for them.

I would expect there is much greater chance of infection from your camlock fittings if they haven't been cleaned properly than through the surrounding air not being filtered.

In terms of simply drilling holes in a racking cane - that doesn't really introduce the air - Makes the wort go all over the place but it isn't really making use of the venturi principle to suck air in.

Keep us posted on how you go.


Cheers

Roland

I'm pretty sure white rabbits open fermenters are in a pretty controlled environment, with HEPA filtered air etc? I might be wrong though. Open fermenters work because the krausen acts like a protective shell, shielding the beer underneath. I'd bet they still use sterile filtered O2 to oxygenate their wort.

When you aerate wort using a stone, the idea is to get really fine air bubbles, which increases the surface area of the air and allows it to be absorbed by the wort more effectively. All of these designs dont do that so i'd imagine the O2 uptake would be less. I think if using air to oxygenate, you really need to do everything you can to get as much dissolved as possible, so i would suggest an aeration stone somewhere in your set up

 

[puffer555]

I'm pretty sure white rabbits open fermenters are in a pretty controlled environment, with HEPA filtered air etc? I might be wrong though. Open fermenters work because the krausen acts like a protective shell, shielding the beer underneath. I'd bet they still use sterile filtered O2 to oxygenate their wort.

When you aerate wort using a stone, the idea is to get really fine air bubbles, which increases the surface area of the air and allows it to be absorbed by the wort more effectively. All of these designs dont do that so i'd imagine the O2 uptake would be less. I think if using air to oxygenate, you really need to do everything you can to get as much dissolved as possible, so i would suggest an aeration stone somewhere in your set up

I agree with both of you to some extent.
The racking cane with holes is how the yanks do it (link above).
Seems to work well.

Maybe airborne infections are not such a problem.
However I filter my air currently which I believe is standard practice for those who use airpumps.

I was just trying to use the venturi method with filtered air.
Based on results in US, I think its a good idea.

Remember that all the wort passes the venturi too.
Not just the small amount that is exposed with an airstone in the fermenter.
Should allow for greater aeration.

Any other thoughts?

 

[Jazzafish]

Hi,

I would do a cost/benifit ratio of using bottled pure oxygen before building/having something made. According to the recent Yeast book by Jamil Z and Chris White, pages 76 to 83 argue that pure oxygen is simply the superior way to do this. Faster and safer.

Most breweries use an inline aeration system post chiller to inject pure oxygen as they pump into a sanitized fermenter.