Did I accidentally oxidize my brew?

[mjrinkenbaugh]

So, I just kegged a brew that I'm entering into a private homebrew competition. My first competition ever! I decided to attach the CO2 and shake to get some carbonation going quick since I want to taste in a day or two to know if it's worthy enough to enter, but I forgot to purge the keg's headspace before shaking! I did however fill the keg with StarSan solution yesterday and pushed it through the lines with CO2 before kegging today, so most of the air that was in the keg should have been CO2. Has anyone done this before? How did your beer come out? Any other comments??

Thanks! Cheers!

Mike

 

[mongoose33]

You're fine. You probably had maybe a pint or so of headspace left (maybe 2 pints to be safe). By purging the keg of Star San you left only 21 percent of a pint or two of air. Not a whole lot. Then you mixed that small amount of left-over air with an entire keg of CO2, which then was again pushed out.

I think much has to do with how much hoppiness you have in the beer, as O2 is the enemy of hoppiness.

Next time, purge the keg when it's full of star san (several purges) which will get most of that headspace cleared of air. Then when you push out the star san that little remaining air will mix with the entire keg full of CO2, which then will mostly be pushed out by the beer. The resulting proportion of oxygen left will be tiny.

 

[mjrinkenbaugh]

Well, here's another couple of details. Keg "full" of StarSan is a bit of a stretch. I used 1 oz of StarStan and filled the keg half way, so it had oxygen in half the keg when I pushed it out, but I also installed new beer lines at the same time, and I ran a little bit of extra CO2 through the lines after the keg was emptied so that I wasn't leaving excess sanitizer in the lines. Also, this batch came up short on volume. It was my first time trying BIAB instead of fly sparging and there was lots of grain particles and trub to get settled out. I think I came out to 3.5 gallons instead of 5. I'm guessing maybe I'm still ok. This was not a hoppy beer, it's a brown ale / saison mix (isn't that interesting?) Lol!

 

[mongoose33]

Well, here's another couple of details. Keg "full" of StarSan is a bit of a stretch. I used 1 oz of StarStan and filled the keg half way, so it had oxygen in half the keg when I pushed it out, but I also installed new beer lines at the same time, and I ran a little bit of extra CO2 through the lines after the keg was emptied so that I wasn't leaving excess sanitizer in the lines. Also, this batch came up short on volume. It was my first time trying BIAB instead of fly sparging and there was lots of grain particles and trub to get settled out. I think I came out to 3.5 gallons instead of 5. I'm guessing maybe I'm still ok. This was not a hoppy beer, it's a brown ale / saison mix (isn't that interesting?) Lol!

Well, that changes everything. You're absolutely, utterly, and without a doubt S.O.L. That beer is probably so oxidized it'll probably burst into flame upon the first attempt to serve it.

J/K. I don't think it'll matter much. I still think you'll have drinkable beer, maybe very good beer. Some of my early beers, before I became more focused on reducing oxygen exposure, were very well received by others--in addition to tasting very good to me.

That said, I'd probably put it on a schedule to drink it sooner than later, and you know, now, how to reduce such exposure. Drink it, be happy.

 

[IslandLizard]

Your young beer will taste probably fine, but with time the oxidation may become more prominent. Storing it cold in your keezer will slow down the oxidation process somewhat. Whether the beer is competition worthy is your call. If the fee for admission is low it's probably worth a shot. Would be interesting to see if the judges pick up on your little mishap.

One question, why do you use Starsan at double strength? One ounce per 5 gallons is the recommended dosage. It won't work any better if stronger, but you leave 2x as much behind as you normally would.

 

[mjrinkenbaugh]

Whoops. I totally did say 1 oz. StarSan to half keg (2.5 gal), but I meant .5 oz to half keg. I don't use StarSan at double strength.

 

[jddevinn]

Technically yes, you are beyond the generally recommended ppb of O2 at packaging. What type of beer? How long to competition? How are you bottling? You may be OK, but not as good as you would have been with a proper purge.