something WILD in my keg?

[laserghost]

after about 30 batches into my brewing career, i think i may have finally gotten something wild in beer.

a little over a month ago i brewed a big, hoppy 1.070 amber that sat in primary carboy for a month before i racked to a secondary carboy with the intention of aging for a bit before serving. i ended up only leaving it there 10 days before racking to the keg to dry hop. dry hopped in the keg for 7 days and yesterday i decided to pull the bag out and move it into the kegerator.

here's what happened (this has never happened to me before): moved the keg into the kitchen from where it had been sitting at 70 for a week with CO2 in the headspace. started letting the gas off to lift the lid and foam starts spraying out of the release. there was way more gas than i was expecting, and i had to keep releasing gas and lots of foam, which was now forming a messy puddle of beer on the floor.

finally, got the lid open and pulled the bag and couldn't even see the beer surface under a thick head of white foam (krausen?). decided to pull off a sample with my thief (soaked in star san), and then quickly resealed the keg and purged headspace with CO2 and put it in the kegerator to chill.

_________________________


Sample tasted great – the best this beer has tasted yet from the samples, but I'm still concerned because the gravity had dropped from being done as dirt at 1.019 for weeks, now down to 1.016 and the sample was real foamy and releasing gas bubbles.

I couldn't see any visual signs of the beer's surface through the foam in the keg, so I don't have many visual clues.

I'm trying to find some sort of explanation as to 1) where it could have come from 2) what it will do to the beer 3) how to prevent it from happening again

_________________________


more info on process:

i am super into being as sanitary as possible. i soak all my gear in oxyclean and scalding water to clean and then run star san through everything. to clean my kegs after use, i soak them full with oxyclean overnight and then before filling them i soak in star san and drain upside down in the bucket.

i have a keg lid with hook welded to the inside to hang a dry hopping bag, which is a 5 gal paint strainer bag w/ ss nut to weigh it down. i only use the bag for hops and i soaked it in star san several minutes before filling with hops, in the keg and sealing up.

i purged the keg with CO2 before racking from secondary.

this was the first time i've ever used a secondary, but there was no visual change or formation in the secondary. gravity didn't budge.

the first notice of anything weird was after dry hopping and being in the keg.

_________________________


perhaps i didn't get the keg as clean as i had thought? maybe the bag introduced some bug? maybe something (a fruit fly?) flew in during racking?

finally, when i was dry hopping in the keg, i recall dropping the bag in the keg and i had to stick my arm in to retrieve it quickly … maybe some of my wild arm hair yeast dropped in and survived the star san and CO2?

my current plan is to just start drinking the beer soon and see if i notice any negative shifting in a few weeks, maybe the cold temps and CO2 will stop any more fermentation?

any one have any thoughts on this?

 

[duboman]

My guess is that racking to the keg roused the yeast and restarted what proved to be a stuck fermentation.

If it was an infection the beer would not have smelled or tasted like the good beer you described and since the keg was not chilled the yeast continued to ferment the beer

 

[laserghost]

Thanks for the vote against infection!

But if it was stuck fermentation, I wonder why racking to secondary wouldn't have restarted it. I swirled the carboy at towards the end of primary to rouse the yeast.

Also, this was a fifth gen American Ale II starter on stir plate and I used pure O2 before pitching. Haven't been stuck before with this yeast (that I know of).

I hope you are right!

 

[Trail]

I wonder why racking to secondary wouldn't have restarted it.

'Cause yeast be cray-cray.

Could have been a temp swing. Could have been insufficient oxygenation at pitch (which could mean bad things here.) Could be a steep and strategically positioned temp gradient in your fermenter. Could be a mutation in your fifth-generation cake. Could be a pack of domovoi. Who knows?

Forget about it, laserghost. It's chinatown.

 

[laserghost]

ahhh, yeast. you crazy little bastards ... i love you like a sonofabitch!

i'll report back if the batch goes south. if you don't hear from me, consider it in good health.