Krausen or Mold?

[thevalor]

An age old question, I'm sure. When I made cider, I never saw any of this, but my friend has some left over gunk on top of his cider after fermentation. Fermenting 2 weeks with champagne yeast and yeast nutrient. I suspect this is just the remnants of some happy yeast.

 

[eliastheodosis]

I'll go first. Yes, those just look like some random yeast rafts to me. It's hard to see super clearly from the pics but they seem isolated. Not a concern in my mind. If he's worried about it then he can wait for a short time to see if it evolves.

If the ferment is pretty much done then I'd caution against opening the top too much to check on it, though. He'll just be exposing it to oxygen each time. I say let it sit until he plans to bottle. Open it and if it looks okay/similar then bottle. If it's growing then probably don't.

 

[doublejef]

Krausen.