Black ring on yeast starter- cause for concern?

[green_giant43]

I am making two 2L yeast starters for my Oktoberfest coming up since i don't have a 5L flask or anything (that and the packets are old).

Anyway, both flasks were cleaned and sanitized before use. Both had 1.035 OG at the start and have been fine. I topped them both with aluminum foil. The one is doing just fine. The other looks like this-

It's a fine black ring (sorry for the quality.) At first I thought of a dreaded fruit fly infestation but it looks just like little shavings and almost like a normal krausen. The DME I used was Briess light so I don't know why it would ever look like that.

Do I have to worry about this? I was gonna cold crash, decant, and pitch. I think it should be fine (doesn't look like an infection) but not sure if anyone else has seen this.

 

[IslandLizard]

Shavings of what? Aluminum?
Are you using a charcoal filter anywhere in your water supply?

It's probably just fine.

 

[green_giant43]

Shavings of what? Aluminum?
Are you using a charcoal filter anywhere in your water supply?

It's probably just fine.

No charcoal filter. Just tap water from the sink. Other starter is clear. The absolute only thing I can think of is maybe shavings from the pot I was using to boil the water (which I funneled into the flasks.)

Now that I think about it. It probably is that as I was trying to keep the DME from scorching. I've never noticed shavings when cooking regular food but maybe. I think it'll be fine then. I'll just pour that off I guess.

 

[IslandLizard]

Yeah, you'll be decanting it off, anyway. Take a look at that pot, though.

 

[brewing_clown]

I wouldn't use it. The risk of infecting a batch is too great IMO.

 

[IslandLizard]

I wouldn't use it. The risk of infecting a batch is too great IMO.

What kind of infection do you think it can be?

Aren't both from the same wort, that was boiled? Unless the flask was unsanitary, where else could it have come from?

 

[brewing_clown]

What kind of infection do you think it can be?

Aren't both from the same wort, that was boiled? Unless the flask was unsanitary, where else could it have come from?

Well, if they came from the same pot, and one has a black ring and the other doesn't, wouldn't there be a good chance that the issue didn't start in the pot?

 

[IslandLizard]

Well, if they came from the same pot, and one has a black ring and the other doesn't, wouldn't there be a good chance that the issue didn't start in the pot?

It surely is a curious case. Maybe the OP can do some more detective work to the black ring's origin, and report back to us.

He could have poured the black residue into one, not the other. Let it sit for a week and see if it grows?

 

[brewing_clown]

Either way, pot residue or not, I wouldn't risk pouring into my wort. That's just me though. I hate dumping beer.

 

[Talgrath]

It's hard to tell exactly from the picture, but it kind of resembles black mold that we get up here in Washington, which does tend to like damp, cool places. I know one thing, I sure as hell wouldn't let that anywhere near my beer.

 

[green_giant43]

You can see it sometimes come up in the beer. And my only thinking is that when I funneled into the flasks, I funneled the last remnants into that one flask.

 

[JonM]

Huh. That's weird. If you turn off the plate, does the black stuff settle to the bottom?

 

[nicolas_james]

Looks like last time I slightly scorched some DME in my starter

 

[green_giant43]

Huh. That's weird. If you turn off the plate, does the black stuff settle to the bottom?

Will try that tonight. That's gonna make it about 2 days on the plate so I had planned on turning it off tonight and crashing it before brewday on Sunday. I'm leaning towards stuff off the pot or scorched DME. I would be very surprised that this one would have a mold like infection but the one sitting directly to the right of it doesn't.

 

[green_giant43]

Duplicate post

 

[green_giant43]

Didn't seem to fall really. Sitting on top currently. The consistency is almost like metal shavings. I could see it being that or the scorched DME. Not sure. Gonna let it cold crash and see what it looks like tomorrow and Sunday when I brew.