Whats a yeast cake?

[Martin the fish]

I've heard this 'yeast cake' phrase bandied about on the forum but i have no idea what it is.
I quite like a bit of cake But i presume it's like a yeast culture sort of thing?

[steve_flack]

It's the yeast left at the bottom of a fermenter once you've racked the beer off it.

[Martin the fish]

What do you do with it?

I've always thrown mine away?

[steve_flack]

Depends. Usually I throw it away (always if I've used a dried yeast) unless I'm using a brew as a steeping stone to a bigger one. Say if you brewed a Belgian Pale Ale (and so would have used a liquid yeast) to grow yeast up for a Tripel or something. There's an element of risk doing that as you have to have been super clean as bugs multiply quicker than yeast and there's always a possibility of transfering bugs to the bigger beer.

With dried yeast don't bother. Dried yeast is cheap and you can always pitch another pack if you need more yeast. It's not worth the risk with dried.

[Martin the fish]

Thanks for the explanation.

[oblivious]

You can also wash the yeast and save it for another brew, only worth doing with liquid yeast.

Yeast washing