Oxygen reg & stone

[Chris Craig]

I picked one of these wort aerators up on eBay a few days ago. Should be here next week.  It hooks up to a standard disposable oxygen bottle that you can get from the hardware store for $10.  

http://www.ebay.ca/itm/360498130899?ssP ... 2336wt_952

Anybody use one?  Tips or warnings?

[jeffsmith]

Nice find on the price and shipping, definitely the cheapest I've seen yet. Just grabbed one myself as well as I'd been looking for a while.

[Chris Craig]

Really hope this comes in this week.  I want to brew on Monday, and it'd be nice to try it out.

[jeffsmith]

Still waiting on mine as well. PITA that USPS tracking drops off as soon as the package hits the last US point on the journey.

[jamie_savoie]

I bought a stone awhile back and now I need to buy a regulator....it's getting old shaking the fermenter for 10 minutes lol

[chrismccull]

I just use an aeration paddle, it seems to work fine.

[Chris Craig]

I just use an aeration paddle, it seems to work fine.

I've read that you need about 10ppm oxygen for optimal yeast performance.  By shaking or using a paddle, the most you can hope for is 4ppm.  I'm not saying you can't make great beer without using an oxygen bottle, it just reduces lag time, and makes the yeast healthier throughout the fermentation reducing the risk of contamination.

[chrismccull]

Good to know.

I've always found that the paddle works well, but, never knew how much O2 it added.

[fakr]

I've been using oxygen and aeration stone for some time now.

my rules of thumb have been:

-any OG under 1.046, I don't bother with oxygen.
-OG 1.050 to 1.060, hit with oxygen for 30 seconds
-OG 1.060 to 1.070, hit with oxygen for 40 seconds
-OG 1.070 to 1.080, hit with oxygen for 50 seconds, etc.
-boil aeration stone before use.
-use a gas hose that fairly easy to remove from the stone.....hoses don't take to boiling very much.

The amount of oxygen to OG ratio I mentioned above isn't necessarily optimal or ideal, but it's what I've set as a constant.

I will say, there is a noticeable fermentation lag period in high gravity wort when I don't use oxygen.

[Chris Craig]

I've been reading the book "Yeast". It says to use about 2 minutes at 1 litre per minute flow rate. I have no idea how to gauge this though.

[fakr]

2 minutes for 5 gallons?  wow, that's much higher than I've read.  I've heard up to 2 minutes with regular air though.

[Chris Craig]

I'll look it up again and post what I find. I could be mistaken.

[Chris Craig]

From Yeast: A Practical Guide to Beer Fermentation by Chris White and Jamil Zainasheff:

To help homebrewers with the question of how much oxygen to add to a batch of beer, White Labs ran an experiment injecting pure oxygen into 5.4 gallons of 1.077 wort using a 0.5 micron stainless steel sintered stone at a flow rate of 1 litre per minute. The results show that to reach the desired 8 to 10 ppm, you would need to inject oxygen for one minute.

Shaking, 5 minutes = 2.71ppm
30 seconds O2 = 5.12 ppm
60 seconds O2 = 9.2ppm
120 seconds O2 = 14.08 ppm

and...

To demonstrate the effect of varying dissolved oxygen levels on fermentation, White Labs then pitched WLP001 at a rate of 12 million cells per milliliter into the worts from the dissolved oxygen tests.  The wort samples around 3 and 5 ppm of oxygen did not attenuate as fully as the other samples, which attenuated a full degree Plato over the shaken sample.

They go on to say that the optimal O2 level is tied to the yeast cell count, which should be tied to the OG, so fakr is right, the bigger the beer, the more oxygen required.  They also say that really big beers benefit from a second hit of oxygen after the first few hours.

Now, I have no idea how to achieve a 1 litre/min flow rate from these regulators.  Maybe full-open is 1 litre/min?  either way, about 40 - 60 seconds should be good for most beer.

[fakr]

I think I got my info from the following wyest article:

http://www.wyeastlab.com/hb_oxygenation.cfm

it mentions near the bottom the absorption rates of O2 according to what method of aeration is used.


I think that's where I got my info...and according to the info, looks like I might be under aerating my wort.  Then again, it doesn't mention flow rates.  I think I'll aerate a litle longer and see if there is a noticeable difference.

[sdixon]

I have been thinking about getting an aeration stone as well. My lag times drag on sometimes... opening myself up to potential contamination.