Homebrewers Association | AHA Forum

General Category => Yeast and Fermentation => Topic started by: astrivian on June 09, 2010, 04:19:02 PM

Title: oxygenation tips
Post by: astrivian on June 09, 2010, 04:19:02 PM
I am curious as to what strategies you all use for oxygenating the wort. What i usually do is pour the wort back and forth between two buckets about 5 times. Do you think that is sufficient?

Also, there is something i never quite understood about this: Do you oxygenate when the wort is hot or cool? I have been doing it when the wort is cool just before i pitch but i think i have read some people say they oxygenate hot.
Title: Re: oxygenation tips
Post by: bonjour on June 09, 2010, 04:22:06 PM
I use an immersion chiller, when my wort is below 90F I pull the chiller up and down thru the wort increasing the chill rate (via agitation) and aerating the wort at the same time.  Works great, even for really big beers.

Fred
Title: Re: oxygenation tips
Post by: tygo on June 09, 2010, 04:32:13 PM
I usually pick the carboy up and shake the hell out of it for about a minute.  Works well but a little hard on the back and arms.

For really big beers or if I'm fermenting in a bucket I've been using a diffusion stone to blow pure O2 through the wort for 30-60 seconds.

I think pouring back and forth a few times should be fine for most beers.  But wait until the wort is cooled (below ~80-85F) or there could potentially be off-flavors in your beer as it ages.
Title: Re: oxygenation tips
Post by: bluesman on June 09, 2010, 04:38:37 PM
I use a mix-stir rod with an electric drill. It incorporates alot of air in a short amount of time. I find that this method works well for me.
Title: Re: oxygenation tips
Post by: richardt on June 09, 2010, 04:43:40 PM
Fred, do you wait until the temp gets below 80-85F to do that in order to avoid hot side aeration (HSA?)

Astrivian, here's my method:  I just attach a sanitized fine nylon mesh bag to the end of my output hose to filter out any hop particles and then put it inside a SS bullion china cap strainer and large nylon funnel (w/ screen) and have it drain into the better bottle or SS corny keg for fermentation.  All that screen-induced agitation seems to aerate it fine.  And it is a lot less effort physically.  I also do not use O2 bottles, aquarium pumps, or aeration stones.  I have read conflicting accounts as to whether aerating (with air) versus oxygenating (with O2) is better.  YMMV.
Title: Re: oxygenation tips
Post by: tubercle on June 09, 2010, 05:26:36 PM
Wait until its cool. The cooler the better. Liquid has a saturation point for dissolved gasses and the lower the temp the more gas (oxygen in this case) it can hold. That is one reason your are having to oxygenate it the first place. The boiling of the wort drives most of the free oxygen out and now you are having to replace it for the yeast to use.


 That's science as Tubercle understands it.

Title: Re: oxygenation tips
Post by: kramerog on June 09, 2010, 05:41:55 PM
I place a fermentation stone in the kettle towards the end of cooling to aerate and to increase both heat transfer and uniformity of temperature.  I may pitch yeast in the kettle if I'm using the same yeast for the entire 10 gallons and continue aeration to mix everything up.  During the transfer into carboys, I orient the hose so the wort fans out on the side of the carboy to maximize air-wort contact.  The fanning of the wort is a winemaking technique I picked up.  Finally, I might rock the carboys a little. 
Title: Re: oxygenation tips
Post by: bonjour on June 09, 2010, 05:42:55 PM
Fred, do you wait until the temp gets below 80-85F to do that in order to avoid hot side aeration (HSA?)

Astrivian, here's my method:  I just attach a sanitized fine nylon mesh bag to the end of my output hose to filter out any hop particles and then put it inside a SS bullion china cap strainer and large nylon funnel (w/ screen) and have it drain into the better bottle or SS corny keg for fermentation.  All that screen-induced agitation seems to aerate it fine.  And it is a lot less effort physically.  I also do not use O2 bottles, aquarium pumps, or aeration stones.  I have read conflicting accounts as to whether aerating (with air) versus oxygenating (with O2) is better.  YMMV.

Yes,  that is the reason for waiting

Fred
Title: Re: oxygenation tips
Post by: Hokerer on June 09, 2010, 06:00:28 PM
I had to give up on my aeration stone because I couldn't use it as long as I wanted before the foam came out the top. Instead, I just connect the aquarium pump to a racking cane and blow bigger bubbles for a longer time to accomplish the same thing.  No foam issues.
Title: Re: oxygenation tips
Post by: astrivian on June 09, 2010, 08:27:41 PM
Okay it sounds like i am on the right track at least. Most of my OGs are 1.100 or higher but i realized i have been skimping on the oxygenation, which is probably why my attenuation isn't as high as it could be (I just read the "How to brew a BIG beer" article, it is great).

Maybe i will increase the number of times i pour the wort back and forth. Gives a good workout too :)

Also, i used to be into reef keeping and i remember that cooler water will hold more CO2, but i didn't know it was true with all gasses. That explains it well.

I have never tried the air pump, but i have several. Another reef keeping note: When i used to raise phytoplankton we used hard airline tubing attached to flexible tubing to oxygenate the jars. Airstones can harbor bacteria and are often only fully sanitized with a pressure cooker. The hard airline tubing makes relatively small bubbles and is easiest to clean; plus you can get a bigger pump and a gang valve and split one tube into four or eight. You could just use flex tubing but it is hard to manage.
Title: Re: oxygenation tips
Post by: bonjour on June 09, 2010, 08:48:07 PM
(I just read the "How to brew a BIG beer" article, it is great).
thanks
Also, i used to be into reef keeping and i remember that cooler water will hold more CO2, but i didn't know it was true with all gasses. That explains it well.
hold for all gasses at "normal" temps
Title: Re: oxygenation tips
Post by: richardt on June 09, 2010, 09:11:47 PM
... i remember that cooler water will hold more CO2, but i didn't know it was true with all gasses. That explains it well.

Cooler liquid will hold more gas (CO2 or O2 or NO2) than warmer liquid.  Another way of saying it is a warmer liqid holds less gas than a cold liquid.  Keep this in mind when pouring a highly carbonated colder liquid into a warmer glass, bottle, or vessel (=foaming).  Of course, nucleation sites (e.g., scratches, pits, or sugar granules) play a role with the speed at which this occurs.
Title: Re: oxygenation tips
Post by: sienabrewer on June 11, 2010, 03:53:34 PM
I use a mix-stir rod with an electric drill. It incorporates alot of air in a short amount of time. I find that this method works well for me.

+1 that is my method too.  Just be careful not to let the rod hit the bottom of the bucket as you are letting it rip.  It will scratch your bucket, and I know this from first hand experience.
Title: Re: oxygenation tips
Post by: zombywoof on August 03, 2010, 07:09:30 PM
I typically pitch between 75 and 80 degrees. I use a stone with those red oxy bottles you get from HD. I have read many different opinions on how long to oxygenate, some based on temp, some based on OG, etc.. Most of my beers tend toward the higher OG range. I have been increasing the time of late because I don't seem to get as far along in fermentation as I think I should. Is there a "Too Much" when using a stone? Is there a "Rule of Thumb"?
Thanks
Title: Re: oxygenation tips
Post by: bonjour on August 03, 2010, 07:17:53 PM
IMHO 75-80 F is too warm to pitch for almost all beers
ROT i follow is to pitch low and allow the wort to warm up to fermentation temp.

If I pitched my big beers at that temp they would be undrinkable.

Fred

Title: Re: oxygenation tips
Post by: zombywoof on August 03, 2010, 07:27:50 PM
The beers have been fine, so I may have overstated the temp a wee bit!  This summer has been hot and my chiller only gets it down to those temps, by the time I get it into the carboy and get my self together it's probably closer to 70 - 73, not sure. Guess I should actually check next batch. I could wait longer in my basement which is cooler.
Title: Re: oxygenation tips
Post by: saintpierre on August 03, 2010, 07:32:18 PM
I use a mix-stir rod with an electric drill. It incorporates alot of air in a short amount of time. I find that this method works well for me.

I use this method too but I have a mix rod with two fans on it attached to the rod with a pin.  The mix rod fits inside a carboy and when I run the drill the centrifugal force opens the fans.
Title: Re: oxygenation tips
Post by: ndcube on August 03, 2010, 07:34:39 PM
The beers have been fine, so I may have overstated the temp a wee bit!  This summer has been hot and my chiller only gets it down to those temps, by the time I get it into the carboy and get my self together it's probably closer to 70 - 73, not sure. Guess I should actually check next batch. I could wait longer in my basement which is cooler.

Sounds like it's time for a swamp cooler.
Title: Re: oxygenation tips
Post by: bschwoer on August 05, 2010, 12:50:49 AM
Check out Wyeast's technical information on their website for home enthusiasts.

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

They have done studies on different techniques to oxygenate wort.  Their conclusions state that the highest concentration of oxygen a homebrewer can achieve without injecting pure oxygen is 8 ppm.  Their studies also show that splashing and shaking the wort will achieve the same concentration as an aquarium pump with stone.  They conclude the aquarium pump and stone is not an efficient way to dissolve oxygen.

Wyeast also says 10 ppm is a sufficient level of oxygen in most situations.  Bigger beers (higher original gravity) will generally do better with higher levels of DO (dissolved oxygen) to achieve higher attenuation.
Title: Re: oxygenation tips
Post by: gimmeales on August 05, 2010, 04:55:44 PM
my oxygenation technique includes the smallest drop of olive oil possible (tip of a guitar string dipped in the OO) in the starter container on the morning of brewday, then quietly siphon wort into fermenter, pitch yeast  :)
Title: Re: oxygenation tips
Post by: IHBHS on August 05, 2010, 06:34:32 PM
For Oxygenation, I use More Beers oxygenation system with a 1.4oz O2 bottle.  I made an inline oxygenation setup out of a T compression fittings and a couple barb fittings so that the stone sits inside the T and it oxygenates the wort as i am pumping it into the fermenter.  No problem with foaming and the beer has turned out really well.
Title: Re: oxygenation tips
Post by: hopaddicted on August 06, 2010, 03:14:39 AM
The other issue with aerating/oxygenating on the hot side is the oxygen came bond back onto other particles while hot, though cannot while it is at pitching temps (think about 100 degrees was the threshold, but I'll try to dig up the source).

I just dump or siphon through a fine SS mesh for aeration, need to look at a better method.
Title: Re: oxygenation tips
Post by: 1vertical on August 09, 2010, 01:55:05 PM
I use the ss rod with scintilated stone attached to the rod. This allows me to get the stone
easily to the bottom of the fermenter.  I use medical O2 and gas the heck out of the wert.

I give the scintillated "ss stone" a good soak in everclear b4 and after each use. That seems to me to
be the thing for removing bugs in the stone without pressure cooking....but one day I may have to
pressure cook the stone just for peace of mind.
Title: Re: oxygenation tips
Post by: zombywoof on August 10, 2010, 07:41:45 PM
1vertical, how long do you typically "gas" the wort? I typically go anywhere from 60 sec to 80 sec. I've heard you can go into several minutes for big beers.
Title: Re: oxygenation tips
Post by: wingnut on August 10, 2010, 07:59:43 PM
my oxygenation technique includes the smallest drop of olive oil possible (tip of a guitar string dipped in the OO) in the starter container on the morning of brewday, then quietly siphon wort into fermenter, pitch yeast  :)

Since you are makeing good beer, take my comment for what it is worth....

However, I have a hard time getting my head around how the sterols in the small drop of floating olive oil is going to come in contact to ALL the yeast floating around, giving them a chance to adsorb the sterols when they are multiplying.  (Keep in mind the yeast multiply in the first few hours after being pitched). 

If the beer is good, I would NOT CHANGE A THING, but I do not think it is an effective substitute for good aeration.
Title: Re: oxygenation tips
Post by: hopfenundmalz on August 10, 2010, 08:19:15 PM

However, I have a hard time getting my head around how the sterols in the small drop of floating olive oil is going to come in contact to ALL the yeast floating around, giving them a chance to adsorb the sterols when they are multiplying.  (Keep in mind the yeast multiply in the first few hours after being pitched). 

If the beer is good, I would NOT CHANGE A THING, but I do not think it is an effective substitute for good aeration.

This may give some background on the olive oil as a sterol source in place of oxygenation.

http://brewcrazy.com/hull-olive-oil-thesis.pdf

Hope this helps.
Title: Re: oxygenation tips
Post by: 1vertical on August 11, 2010, 04:45:03 AM
1vertical, how long do you typically "gas" the wort? I typically go anywhere from 60 sec to 80 sec. I've heard you can go into several minutes for big beers.

I go a couple minutes I suppose.  I never really timed it since I switched to med grade and bigger tanks.  I used
to go 45-60 secs with the small red tanks. Now I try to put a good thick layer of foam on top of the liquid that has
to stop a lot of the oxygen from coming out of solution and serve to "trap" the gas under the layer of foam.
How much is too much? and what is the detrimental result of too much? I think you just need to get a good
environment for the yeast,no, the best possible environment. :P
Title: Re: oxygenation tips
Post by: wingnut on August 11, 2010, 05:38:53 AM

This may give some background on the olive oil as a sterol source in place of oxygenation.

http://brewcrazy.com/hull-olive-oil-thesis.pdf

Hope this helps.


Wow!  Very interesting paper!  I will have to read it through a few more times to fullly digest it, but it is very intersting.  The only thing that bothers me is the relative increase in some esters.  Esters tend to be an intermediate step in the yeast's manufacturing process, and the elevated levels suggest that there may be a lack of something, preventing the yeast from completing the cycle and getting stuck at the ester production step.  However, since the taste panel did not detect any significant issues, the increased levels are aparently not critical.

How long have you been doing this, and have you tried re-pitching the yeast into other batches?  I am wondering if the Olive Oil is good for one generation of yeast, or if it is good for multiple generations...  Very interesting. 

Thanks for the link!
Title: Re: oxygenation tips
Post by: hopfenundmalz on August 11, 2010, 01:07:12 PM

How long have you been doing this, and have you tried re-pitching the yeast into other batches?  I am wondering if the Olive Oil is good for one generation of yeast, or if it is good for multiple generations...  Very interesting. 

Thanks for the link!

We tried it once, and it seemed to work.  Usually use O2 or sterile filtered air.
Title: Re: oxygenation tips
Post by: gimmeales on August 12, 2010, 03:50:26 PM

How long have you been doing this, and have you tried re-pitching the yeast into other batches?  I am wondering if the Olive Oil is good for one generation of yeast, or if it is good for multiple generations...  Very interesting. 


I've done the OO thing one virtually every batch of beer using liquid yeast I've brewed in the last year or so, since I first read about the procedure...however, that's probably only 5-6 batches since I was using dry yeast quite a bit too.  I drop the OO into the starter and aerate it through intermittent shaking for 8-12 hrs before it's pitched into the wort to help spread the sterols around.  Also, these have been single-generation beers - so can't comment on subsequent re-pitching.

I've had nothing but vigorous, full-fermentations on all those batches with no detectable additional esters.  In fact the only beer that's been 'excessively estery' was according to a judge in a recent comp I entered, but it was a batch in which I used dry yeast  and the temps spiked before I knew it.

I still want to do a test, splitting a batch of wort between three fermenters and treating them as such 1.) normal  wort aeration (shaking) and standard starter 2.) no wort aeration but with OO-treated starter and 3.) no aeration of wort AND no OO in the starter.  The results of that regimen could be quite revealing.

There was a good thread recently on ProBrewer on OO.  New Belgium evidently isn't using the process as standard, but several breweries are and getting good results.
Title: Re: oxygenation tips
Post by: jwatkins56550 on August 13, 2010, 01:43:29 AM
I vaporize ground whole hops, and pump those aromatic vapors through a diffusion stone for a minute or two......just kidding, but I was thinking about that ;)

Title: Re: oxygenation tips
Post by: gordonstrong on August 14, 2010, 04:29:57 PM
That's hilarious.  I'll have to remember that.
Title: Re: oxygenation tips
Post by: ipaguy on August 25, 2010, 03:16:07 PM
After using an immersion chiller, I use a Siphon Sprayer to transfer to my plastic primary.  Seems to work pretty well.
Title: Re: oxygenation tips
Post by: astrivian on August 27, 2010, 04:07:31 AM
Someone might have mentioned this already, but what about using compressed O2? I heard you can buy oxygen canisters at the hardware store. I assume these are meant for cutting torches, and therefore not "medical grade" oxygen. Are they safe? Are they worthwhile?
Title: Re: oxygenation tips
Post by: tubercle on August 27, 2010, 04:33:08 AM
Someone might have mentioned this already, but what about using compressed O2? I heard you can buy oxygen canisters at the hardware store. I assume these are meant for cutting torches, and therefore not "medical grade" oxygen. Are they safe? Are they worthwhile?


The worst O2 is what we are breathing. If you don't mind that then that stuff compressed in a can should be OK too.

 I wouldn't worry about "medical grade". You're not drinking home brew for you health after all.
Title: Re: oxygenation tips
Post by: dak0415 on August 27, 2010, 01:03:08 PM
Someone might have mentioned this already, but what about using compressed O2? I heard you can buy oxygen canisters at the hardware store. I assume these are meant for cutting torches, and therefore not "medical grade" oxygen. Are they safe? Are they worthwhile?
I bought a regulator and .5 micron SS stone from Morebeer (on sale) a couple of years ago and have never looked back.  I did it mostly for the time savings (2 minutes for a big beer, 1-2 for others) and less foam.  Between that and fermentation temperature control, My beers have improved dramatically.  They seem to last a long time too -  20+ batches per tank.  I was hoping for 10.
Title: Re: oxygenation tips
Post by: astrivian on August 28, 2010, 03:12:26 AM
I wouldn't worry about "medical grade". You're not drinking home brew for you health after all.

HA! Good point!  ;D