Commercial beer yeast

[Ktsandven]

Can you harvest yeast from all commercial beers? If not how do you know which ones are bottle conditioned?

 

[FloppyKnockers]

Some, yes. Some, no. Some of the bigger guys filter or use centrifuges to remove yeast. On every brewery tour I've been on no one would tell me what yeast they use. They'll tell me who supplies it, but then tells me it's a proprietary strain blah, blah, blah. The ones who bottle condition are obvious. They'll tell you so on the bottle so you're not surprised when the snot rocket comes out at the end of the pour. IMO, not worth the effort.

 

[Blue-Frog]

Simple answer:
If you see live yeast, it was bottle carbonated.
If you see dead yeast, it might have been bottle carbonated.
If you don't see any yeast, it was not bottle carbonated.

The assumption is if you see yeast in the bottle,
its there because it is leftover from being bottled conditioning.

Of course, it could just be dead yeast added to artifically carbed
(or non-bottled conditioned naturally carbonated) beer.

 

[Bosh]

Sometimes they filter out the brewing yeast and then seed new yeast at bottling so even culturing the dregs of bottle conditioned beer won`t always get you the right yeast.