This week I take a look at the Anvil Oxygenation Kit (aka Aeration wand) which lets you aerate your Wort using pure Oxygen without spending a ton of money. The oxygen wand is actually my favorite new brewing toy and I’ve used it on beer, meads, wines and cider with great results.
The Importance of Aeration
I’ve written extensively on how important aerating your wort before pitching your yeast is to for proper fermentation. Boiling removes most of the oxygen from the wort, and yeast cells need oxygen during the early “lag” phase when they are rapidly reproducing. Ideally you want to get 8-12 part per million (ppm) of oxygen in the wort before pitching your yeast. Having the proper oxygen level leads to faster startup, more robust yeast cell walls and less stress on the yeast.
While you can aerate your wort by shaking or injecting air using a small aquarium pump, neither of these methods will get you all the way up to the 8 ppm minimum needed. For that you need pure oxygen.
The Anvil Aeration Kit
For many years I put off purchasing an oxygen aeration system due to the high expense of buying an oxygen tank, regulator and aerator. However now many companies are producing “aeration wands” which are usually stainless steel tubes with a very fine (typically 0.5-1 micron) aerators at one end. These are immersed directly in the fermenter right before you pitch your yeast. In a relatively short time of 60-90 seconds you can reach the ideal 9-12 ppm for most worts, though a very high gravity wort (1.080 or higher) might take a little longer.
With the wand you purchase either with a standard oxygen regulator to use with a large oxygen tank, or a small oxygen regulator suitable for use with disposable oxygen tanks used in small welding kits. The disposable bottles sell for about $10 at Home Depot or Lowes. Note that these small bottles are not technically “food grade” oxygen so you may want to consider a small inline filter if you go with the small bottles. Also the small bottles only work for a few batches so if you brew a lot you may want to consider a commercial size oxygen tank.
Many vendors sell similar kits, but I went with the Anvil aeration kit from Blichmann (affiliate link) which is a very simple regulator, tubing and aeration wand. It is 100% stainless so you can immerse it in star-san or even boil it to sanitize if you like.
Using an Aeration Wand
I aerate my wort or must right before I pitch my yeast. All you need to do is attach the oxygen tank to the regulator, remembering that the small disposable tanks use a reverse thread so you need to turn them counterclockwise to tighten. Sanitize the wand so you don’t bring along any infections. Next immerse the want in the wort and slowly turn it up until you see light bubbling on the surface. I prefer to run mine at about this flow rate as most of the oxygen is going into the wort and not being blown out the top surface.
Unfortunately you don’t have a flow gauge on these simple systems so you need to guess a bit. John Blichmann recommended aerating for 60-90 seconds to get to 9-10 ppm unless I’m brewing a very large beer (or wine or mead) above 1.080 in which case I might run it 2 minutes. High gravity worts absorb the oxygen slower and also require more oxygen. I’ve also found references saying very high gravity worts/musts such as mead or wine might also benefit from a second oxygen addition within 12 hours.
And that’s it – just remove the wand, pitch your yeast and enjoy a healthy fermentation. Don’t forget to clean the wand thoroughly or even blow a little oxygen into your cleaning solution to make sure it hasn’t picked up any wort or must.
What About an Inline Aerator?
I did take a look at the various inline aerators that many vendors sell and are used in many commercial systems. These are typically fittings inserted into your wort transfer line that essentially aerate the wort as you are transferring it from the boiler to fermenter. To a large degree these have many of the same problems as the aeration wand as they typically don’t have a flow meter, and unless you know the flow rate for both your wort and oxygen tanks (like a commercial brewer might) its difficult to tell how much oxygen you are really adding. You also have the added complexity in assuring the aerator has been properly cleaned after use.
To me the oxygen wand seemed like a simpler solution for the average home brewer, and honestly I love this thing having used it on beer, mead, cider and wine up to 10 gal batches (38 liters) with good results! I can aerate wort in as little as 60-90 seconds and since I started using it my fermentations have started quickly and finished strong. For more challenging fermentations like high gravity beers, wines and meads proper aeration is critical for getting a good strong start.
I hope you enjoyed this week’s post. Thanks for joining me on the BeerSmith Home Brewing Blog. Be sure to sign up for my newsletter or my podcast (also on itunes…and youtube…and streaming radio station) for more great tips on homebrewing.