Purple beer? Oxidation?

[benbradford]

Something interesting happened a few weeks ago. I made a batch of Belgian American ale and split it into 3 vessels from the fermenter. 3 gallons went into a small carboy for intentionally souring, 5 in a keg for serving and another two in another keg. I have made this recipe 3 times before, but this is the first time that I transferred using co2. I pushed co2 into the fermenter and it pushed the beer through the wand and tubing into the kegs... All went well until the last 2 gallons. At that time, the leaf hops from the dry hopping started clogging the wand. I had to pull it out and unclog it at least 10 times and there was also quite a lot of bubbling and burping co2 and splashing beer inside keg.

What was strange is when I went to pour it 20 or so days later, it had turned purple/grey/black. Flavor was off, but at the time I didn't really think cardboard. I am assuming that I oxidized it quite a bit with the splashing and the screwed up transfer.

Any thoughs?

 

[ajdelange]

Infection.

 

[Scubadude918]

Well, no known pathogens can grow in beer due to the pH and alcohol levels, it won't make you sick. So if it tastes good enough to drink, then personally I wouldn't dump it.

As to what caused the color change, I haven't experienced that before. So I can't really help with the "why" factor. I've had beers splash a decent amount and haven't had that problem.




____________________________
Primary: Cider
Secondary: Killer Kölsch

 

[benbradford]

I considered the infection part, especially since I have brought the bugs into the brewery so to say. Didn't taste like any that I have encountered. What infection changes the color if the beer, but doesn't taste like lactobacillus. Actually there was no film on top either.

 

[ajdelange]

I can't really give you an answer there but hazarding a guess I'd go for some sort of mold.

 

[SpeedYellow]

Was there any copper or brass in contact with the beer?

 

[benbradford]

No copper or brass... Already dumped it. Drinking something that you know is incorrect is difficult to say the least. Isn't the most beer that I had to dump

I figured infection or oxidation, but with no other examples of this occurring, I was stumped. I have brewed hundreds of gallons and this isn't like I did anything too out I the usual.

 

[coho3]

No copper or brass... Already dumped it. Drinking something that you know is incorrect is difficult to say the least. Isn't the most beer that I had to dump

I figured infection or oxidation, but with no other examples of this occurring, I was stumped. I have brewed hundreds of gallons and this isn't like I did anything too out I the usual.

Did you ever find out what was causing this to happen? I am now on my fourth batch of this phenomenon occurring and it is almost kicking me out of homebrewing.

 

[Gnomebrewer]

Did you ever find out what was causing this to happen? I am now on my fourth batch of this phenomenon occurring and it is almost kicking me out of homebrewing.

Benbradford hasn't been on the forum for 2.5 years, so a response is unlikely. There are other discussions about grey beer, which is mostly attributed to oxygen. 'Black' would presumably only be from contamination. Purple would mostly like be from a rogue smurf falling in the mash tun.

 

[Gnomebrewer]

To help narrow down your issue, can you describe your process? More detail = better.

 

[VikeMan]

Did you ever find out what was causing this to happen? I am now on my fourth batch of this phenomenon occurring and it is almost kicking me out of homebrewing.

There have been several threads about purplish (purlpe/brown) beers (all IPAs, IIRC) on another forum. In those threads, signs pointed to oxidation. OTOH, lots of pretty well oxidized beers don't turn purplish, so if I had to bet, I'd guess there's more than one factor involved.