Solved my oxidation woes

[jddevinn]

I do virtually the same thing with a small tweak. I noticed that the pressure relief hole sticks down into the lid quite a bit, trapping a LOT (well a relative 'lot' if you're shooting for shelf life) in the lid.

I cut the gas tubes flush so I could tilt the keg at a 45 with the gas post up while filling. As I pump Star-San into the liquid post, it will rush out the gas side and into another keg. I shake it slightly as this is happening until I see no bubbles. The air under the lid will eventually get pushed out

It was shocking how many bubbles will come out AFTER you think it's full. There is still a good amount of air trapped once you're "full" and overflowing the PRV and gas post.

This still doesn't address the dissolved O2 in the StarSan that will start coming out of solution as you push it out with CO2, but it's a huge start.

I've been shaking like crazy to get that air bubble out lately and been trying to come up with a better way.

I've taken to boiling ~6 gallons of water, then adding 100 mg/l SMB (so that the sulfate reacts with any adsorbed O2), then dosing with StarSan. I then use this to purge the kegs and don't have to worry about the dissolved O2 in the StarSan. I'll keep it stored in the last keg that I cleaned for about a month or two before moving it to my general use StarSan bucket and making another batch or degassed StarSan.

 

[user 204491]

For my brewing practices I try to walk the line between ease of use/time efficiency and sound brewing science that produces good beer. For me kegging is about a 10 minute affair, and I never wind up with oxidized beer.

When a keg kicks it gets set aside until I've got several empties, and then I just spend an hour or so one afternoon cleaning them all.

When they are clean I fill each with about 1/2 gallon of Star San and give them a good shake to sanitize.

Then I apply CO2 @ 30PSI for 10 seconds or so.

Then I use a picnic tap to pour off a little Star San ensuring that the dip tube is also sanitized.

Now I have a clean, sanitized, and pressurized keg.

When it's time to keg something I grab one of those kegs and pull on the PRV. If gas comes out then I know everything is good to go. If not, then I set the keg aside to investigate later where the CO2 leak is.

I then use the picnic tap to drain off all of the Star San. From there I simply gravity transfer from the spigot on the fermenter into the open keg.

I then purge @30 PSI 15 times and set the keg to carbonate.

CO2 is stupidly cheap here ($13 for a 20lb exchange), so it doesn't really concern me how much I use.

 

[wobdee]

I've been having good luck lately gravity feeding, adding 10mg/l SMB to the keg and force carbing. Kegs seem to stay fresh for as long as I need them.

 

[ParanoidAndroid]

How would one go about bottling a portion of the finished beer?

I like to keg the majority, but bottle about 5-10 beers. It seems like kegging the whole thing and keeping O2 down is fairly straightforward with a few ways of doing it (Early ferm transfer with spunding, CO2 fermenter transfer, several purges of the keg, starsan purges, etc). But bottling inevitably will expose some beer to oxygen. Then if you want to do both with a batch, it just complicates things more.

 

[mongoose33]

How would one go about bottling a portion of the finished beer?

I like to keg the majority, but bottle about 5-10 beers. It seems like kegging the whole thing and keeping O2 down is fairly straightforward with a few ways of doing it (Early ferm transfer with spunding, CO2 fermenter transfer, several purges of the keg, starsan purges, etc). But bottling inevitably will expose some beer to oxygen. Then if you want to do both with a batch, it just complicates things more.

You can use something like the Last Straw bottle filler from Northern Brewer, which allows for a shot of CO2 into the bottom of the bottle. Or, when I don't want to break out all the equipment, I use a "poor man's" bottle filler such as threads on here describe--and where I learned to make one.

EDITED TO Add: https://www.homebrewtalk.com/showthread.php?t=24678

And my own:



If you allow just a little bit of foam at the top and then put on a cap, that foam will displace air, leaving a headspace virtually devoid of oxygen.

I also have a growler filler that fits my taps; I've also bottled using that, but those are for nearly immediate consumption.

 

[beersk]

I'm curious if adding a little fresh yeast/krausen, say 100mL to the keg before transferring would do the trick.

 

[pvpeacock]

I'm still not convinced all this extra work is necessary, but I also do not believe in man-made global warming either.

 

[UndeadFred]

I might be an oddball, but if I have time and it's not a style that it could be detrimental (clarity) to, I always prefer to sugar prime my kegs. I didn't know why I thought it tasted better until I read the LODO stuff on the other thread (and I am skeptical on a lot of that, still).. but I think at least doing a little priming is superior to purging, and that is why. I now make sure I always make enough to fill the keg up as much as possible. I have been known to make 6 gallon batches to get five in the keg and a few in bottles... cheers....

 

[Derp]

It would be interesting to see Brülosophy or one of the homebrewing magazines do an extensive study of scientifically measured, differing amounts of oxygen in beer over a period of days/weeks/months. That could be followed by experiments on different ways of reducing oxidation (priming, purging, etc.)

I don't want my beer to degrade in days, I'd rather it not degrade too much over weeks, but it would be great if my kegs would stay somewhat fresh for several months. Help me, scientists!

 

[jddevinn]

It would be interesting to see Brülosophy or one of the homebrewing magazines do an extensive study of scientifically measured, differing amounts of oxygen in beer over a period of days/weeks/months. That could be followed by experiments on different ways of reducing oxidation (priming, purging, etc.)

I don't want my beer to degrade in days, I'd rather it not degrade too much over weeks, but it would be great if my kegs would stay somewhat fresh for several months. Help me, scientists!

The oxygen reacts quickly with the wort/beer so the concentration should dissipate as it binds and reacts.

 

[Derp]

The oxygen reacts quickly with the wort/beer so the concentration should dissipate as it binds and reacts.

I meant starting out with differing levels of oxygen and then testing the taste/color over a period of time.

 

[PartagasD4]

I've been having good luck lately gravity feeding, adding 10mg/l SMB to the keg and force carbing. Kegs seem to stay fresh for as long as I need them.

Are you talking "Sodium Metabisulfite" as an antioxidant? I think I remember reading a while back 1 of your post about trying this. So it is working for you then?

 

[wobdee]

Are you talking "Sodium Metabisulfite" as an antioxidant? I think I remember reading a while back 1 of your post about trying this. So it is working for you then?

Yes, I started out with a 6mg/l dose and the flavor and aroma was fading half way through the keg then I upped the dose to 10mg/l and haven't seen a problem since.

 

[PartagasD4]

Yes, I started out with a 6mg/l dose and the flavor and aroma was fading half way through the keg then I upped the dose to 10mg/l and haven't seen a problem since.

Thanks for the reply, I am going to try this Sunday. Would you mind telling me exactly how you do it. I was thinking I would crush a tablet weight out .20 grams for a 5 gal corny and just throw it in. Then do my normal gravity transfer from the bucket spigot to the out post.

I have been topping up with starsan and then push that out. Seal with around 30 lbs so when fermentation is done I have a ready to fill keg. I would lose the seal if I have to open the keg to put the SMB in right?

 

[wobdee]

Thanks for the reply, I am going to try this Sunday. Would you mind telling me exactly how you do it. I was thinking I would crush a tablet weight out .20 grams for a 5 gal corny and just throw it in. Then do my normal gravity transfer from the bucket spigot to the out post.

I have been topping up with starsan and then push that out. Seal with around 30 lbs so when fermentation is done I have a ready to fill keg. I would lose the seal if I have to open the keg to put the SMB in right?

I don't push sanitizer out or do closed transfers. After sanitizing the keg with Saniclean I purge with Co2, rack out from my spigot of my fermenter down to my keg and drop in SMB in powder form once there's a bit of beer covering the bottom.

I have heard of guys doing a closed transfer and injecting SMB solution inline which would probably be better but so far I'm pleased with my results as is. If you go the closed transfer route you probably can get away with less SMB.

 

[jpb2716]

I don't push sanitizer out or do closed transfers. After sanitizing the keg with Saniclean I purge with Co2, rack out from my spigot of my fermenter down to my keg and drop in SMB in powder form once there's a bit of beer covering the bottom.

I have heard of guys doing a closed transfer and injecting SMB solution inline which would probably be better but so far I'm pleased with my results as is. If you go the closed transfer route you probably can get away with less SMB.

I'm interested in doing this as well. Has the sodium metabisulfite added to the kegs affected the beer in any negative ways?

Thanks.

 

[wobdee]

I'm interested in doing this as well. Has the sodium metabisulfite added to the kegs affected the beer in any negative ways?

Thanks.

Not for me but I've heard of others getting a slight aftertaste. Could be you need to figure out a dosage that fits with your system and transfer practices. since I don't do closed transfers maybe I have more O2 for the sulfites to be used up, the same dosage in a closed transfer may or may not have the same outcome?

 

[user 204491]

Yes, I started out with a 6mg/l dose and the flavor and aroma was fading half way through the keg then I upped the dose to 10mg/l and haven't seen a problem since.

Hey, I was wondering if you knew of any articles, research, etc. around this method? I'm quite intrigued, but searching for "sodium metabisulphite antioxidant beer" didn't seem to turn up very much.

 

[wobdee]

Hey, I was wondering if you knew of any articles, research, etc. around this method? I'm quite intrigued, but searching for "sodium metabisulphite antioxidant beer" didn't seem to turn up very much.

I got the idea from the guys over at Germanbrewing.net. they toyed around with it for awhile but went on to spunding. I stuck with it but plan to spund eventually after I get more equipment.

 

[spittybug]

CO2 is heavier than air, right? I'm not understanding how, when filling a corny and thus pushing out 02 during the fill, any small remaining headspace will get much of a chance to oxidize all the beer below it. I usually swap ball valve fittings and bubble C02 through the dip tube to help carbonate it, thus pushing the oxygen out the top..... Of course you don't get it all, but the layers sitting on the beer will be C02 rich, any oxygen will be at the very top. As the keg is drained, the percentage of 02 drops considerably as more C02 is added....... KOW, I've never had an oxidation problem.

 

[day_trippr]

The "CO2 Blanket" thing is a total myth...

Cheers!

 

[jddevinn]

CO2 is heavier than air, right? I'm not understanding how, when filling a corny and thus pushing out 02 during the fill, any small remaining headspace will get much of a chance to oxidize all the beer below it. I usually swap ball valve fittings and bubble C02 through the dip tube to help carbonate it, thus pushing the oxygen out the top..... Of course you don't get it all, but the layers sitting on the beer will be C02 rich, any oxygen will be at the very top. As the keg is drained, the percentage of 02 drops considerably as more C02 is added....... KOW, I've never had an oxidation problem.

Using this logic if you laid down on the ground you would die from lack of oxygen due to all the CO2 in the atmosphere being at ground level cause it's heavier.

 

[doug293cz]

CO2 is heavier than air, right? I'm not understanding how, when filling a corny and thus pushing out 02 during the fill, any small remaining headspace will get much of a chance to oxidize all the beer below it. I usually swap ball valve fittings and bubble C02 through the dip tube to help carbonate it, thus pushing the oxygen out the top..... Of course you don't get it all, but the layers sitting on the beer will be C02 rich, any oxygen will be at the very top. As the keg is drained, the percentage of 02 drops considerably as more C02 is added....... KOW, I've never had an oxidation problem.

Time for today's science lesson. Gases spontaneously homogenize due to diffusion, rather than stratifying by molecular weight. Watch the following video. Br2 is 3.6 times heavier than CO2, and it homogenizes with air in about 30 min (for two ~1 ft tall columns.) CO2 is about the same molecular weight at NO2 (44 vs. 46.) As shown later in the video NO2 homogenizes much faster than Br2. CO2 will behave more like NO2.

[ame]https://www.youtube.com/watch?v=_oLPBnhOCjM[/ame]

Brew on

 

[spittybug]

Wow, I guess I should have EMPHASIZED a few words like "thus pushing out" or "pushing the o2 out the top" or "CO2 rich" (not exclusive) and DEEMPHASIZED the one passage "any oxygen will be at the very top"........ everyone put down the guns...... make beer not war.

 

[RedlegEd]

Yes, I started out with a 6mg/l dose and the flavor and aroma was fading half way through the keg then I upped the dose to 10mg/l and haven't seen a problem since.

Thanks for the dosing info. I just tried this on my Centennial Blonde. Since my scale isn't fine enough to resolve to mg, I dissolved a 550mg Campden tablet (I'm using Potassium Metabisulfite) into 50 ml of water. By my calculations, that gives me ~11mg/ml. I sanitized and racked to my keg as usual, the dosed it with 18ml of the solution (using a 10ml syringe,) then put on CO2 and purging 14 times. Think that'll do it?

 

[mike_g08]

I too have a been thinking of oxidation, after a recent IPA went downhill early.

My proposed process is a hybrid of what I have read:

1. Ferment in bucket. Connect hose from fermenter (in place of airlock) onto liquid out side of keg. Connect airlock to gas (in) side of keg. Goal is to purge keg before use, with "free" Co2.

2. Siphon to above mentioned keg following ferment. Purge headspace several times (at least), then add priming sugar solution for natural carbonation in keg.

This seems simple, and would reduce usage of CO2, while using oxgen absorbing properties of yeast.


An alternate procedure (pressure ferment):

1. Pressure ferment in keg with hose routed to serving keg (for Co2 purging) with spunding valve (set to 12-15 psi) on outlet side of serving keg.

2. crash cool fermenting keg and add gelatin solution into keg fermenter (injection)

3. pressure transfer beer to serving keg (after first drawing off a few pints). Dry hops could have been added to serving keg at the beginning of ferment (step 1).


What do you all think? I think the alternative process would scrub the serving keg more effectively, as the CO2 entering the keg would be at 12-15 psi because of the spunding valve.

Additionally, I have read krauesening is beneficial to remove oxygen and byproducts. That could be incorporated into either process, optionally.