NEIPA turned black!

[jfolks]

This has got to be the most stark color change I’ve ever witnessed in a NEIPA. This is what the beer looked like coming out of the keg after about 3 weeks (glass on right us latest batch, glass on left is 10 days older batch).

This is what the NEIPA yeast harvest / beer looks like in the fridge after those same 3 weeks (sitting next to lambic culture/beer for pale beer comparison)

Grain bill is 2 row, oats, wheat, and flaked barley. London ale 3 and biotransformation dry hop in primary. Sloppily dumped yeast from carboy into jar after transferring the beer sitting on top of it into keg. Jar is sealed tight. Totally stunned at the color change - especially considering it’s coming out “normal looking” out of the keg. What is it about this style that does this?!

 

[murphyslaw]

I've seen threads about these beers darkening, but this seems like something else entirely.

 

[Upthewazzu]

That's...drastic. I stupidly tried to save some harvested yeast from a NEIPA a couple years ago and it turned brown but nowhere near that dark!

 

[Manufacturedevolution]

Weird.

 

[Northern_Brewer]

That’s weird. Seems far more likely to be a bug than something to do with the beer. Does it smell funny?

I certainly wouldn’t use it. In the absence of any other information, one possibility is that it’s infected with a black mould, which is not good as they can produce some nasty toxins. Not saying that’s what it is, just that it’s a possibility that needs to be ruled out.

 

[RPh_Guy]

Seems like a good style to know whether your oxidation prevention strategy is on point!

It's not mold. It would be obvious on the surface.

 

[Northern_Brewer]

Not necessarily- yeast is a mould but can be present without forming surface rafts. Given the potential consequences of black moulds, it would take a lot more than absence of rafts to convince me they weren’t present.

That’s speaking as a former microbiologist who’s worked with a lot of exotic bugs that haven’t read the rule book on how they’re meant to behave.

 

[RPh_Guy]

You've seen mold that can turn a cold, sealed beer a uniform black in 3 weeks without stirring?!? Not sure I'd want to be working in that micro lab. I've never seen or heard of anything like that.

(FYI for everyone not a microbiologist) The "rule book" says yeast have unicellular growth and mold have multicellular growth pattern.
I am not a microbiologist. And I'm not looking for zebras

 

[day_trippr]

fwiw, I had the spent wort in a jar of 1010 turn that color - because I forgot to tighten the lid.
The yeast was still viable...

Cheers!

 

[jfolks]

Doubt it’s contamination - think it’s just good old fashioned oxidation. Fascinating that NEIPA color can turn so drastically given the right conditions.

 

[divrack]

yup. it's not happened to me, but seems to be just what happens to neipas with o2.
admittedly that's the most extreme I've seen, but similar to some photos online. there's a thread here about neipa problems that has similar pics.
I think it's something to do with unmalted wheat and the 'biotransformed' hop particles. I have a question. what was your mash schedule? and was the wheat malted or flaked?

 

[bigbadgreen]

yup. it's not happened to me, but seems to be just what happens to neipas with o2.
admittedly that's the most extreme I've seen, but similar to some photos online. there's a thread here about neipa problems that has similar pics.
I think it's something to do with unmalted wheat and the 'biotransformed' hop particles. I have a question. what was your mash schedule? and was the wheat malted or flaked?

I recall this subject coming up on the beersmith podcast a month or so ago. His guest was talking about neipas and how they can get very dark as the age and are exposed to normal amounts if o2. I think it's just the nature of the style. Have you tasted it to see if that's off. I normally don't suggest tasting beer that's doing crazy stuff but I think it's just a nature of this beer.

 

[jfolks]

what was your mash schedule? and was the wheat malted or flaked?

155 for about an hour
Typically use wheat malt, but use flaked on occasion - can’t remember for sure on this one

 

[Bilsch]

I recall this subject coming up on the beersmith podcast a month or so ago. His guest was talking about neipas and how they can get very dark as the age and are exposed to normal amounts if o2.

Out of curiosity, what is a normal amount of O2?