Reusing yeast

[wegchef]

I probably already know the answer to this question but I'll ask anyways. Just finished a coffee porter, saved the trub in a mason jar and threw it in the fridge. Can I pitch the trub into another batch of beer, replacing the yeast? My first impression is that the coffee flavor will give the next batch that flavor. Am I correct with these thoughts?

 

[lostboysbrew]

you can use the yeast again........as long as there wasnt much beer mixed in with the trub, you should be ok.......it also depends on what your using it for and how big of a batch........

did you sanitize the mason jar???

 

[kanzimonson]

One thing to understand about coffee - part of its flavor comes from suspended particles. At this point, those have definitely settled out and are probably in the yeast cake. Who knows how significant they are?

Secondly, I am a big proponent of proper pitch rates, so if you do reuse the cake, don't dump the entire thing in there. Use Mr Malty to determine how many mL of yeast slurry you need.

I think if you pitched some of the cake into a darker beer you'd be fine. Any coffee flavor that remained would blend with the style and pretty much be unnoticeable. But pitch the right amount!

 

[passedpawn]

Normally I'd say go for it, but the coffee might play havoc with your next beer.

So, I would recommend washing that yeast. Chill and decant (to decant, put in fridge for at least a day or until it separates, pour off liquid). Add some sterile water to the yeast, swirl, decant again.

 

[wegchef]

Sounds good, I'll try washing it after it separates. I did sanitize the mason jar, the trub did fill the entire jar but I wil wait to see how much liquid separates

 

[passedpawn]

Sounds good, I'll try washing it after it separates. I did sanitize the mason jar, the trub did fill the entire jar but I wil wait to see how much liquid separates

Get it really cold (not frozen) and I bet it separates nicely. Maybe give it 2 days. Good luck

 

[ReverseApacheMaster]

You may want to make a starter, decant, add more wort to ferment and decant again (and possibly another run) so that you reduce the amount of coffee flavor particles in the starter. Hopefully you will reduce those components so that there won't be enough to add noticeable flavor.