Whole yeast cake or half?

[Pirate_Pete]

Hi. I've never used the remaining test cake for a next batch so I'm nervous. How long can you save it and is there any method to check if it's still alive? Do you just through all into the new batch?

I leave a bit of beer on the yeast cake.
Then I swirl it around. Pour it into a jar and leave it in the fridge.
Leave the lid slightly loose. It will settle over time, and the missus will ask WTF is this.
Then after a week or so I'll pour a bit of the beer into a 500ml pasta jar.
Pour the rest of the beer away and add the yeast to the pasta jar.
When I come to use it I put some LDME in a demijohn with water and add the yeast for a day or so.
Sometimes I just dump the yeast straight in the brew.
I've used my yeast several times. Just open the lid and have a sniff.
I left the lid tight on one of mine once and it erupted. See below.

I've never put a new brew directly on a yeastcake. I've always thought the FV could do with a clean before starting a new brew. Get rid of the tide line and stuff stuck to the side.

 

[Pirate_Pete]

This is a lager yeast I've had in the fridge for a week.

I'll pour a bit of the beer on top into a jar tomorrow.
then pour the rest of the beer away.
Then pour the yeast into the jar.
Then there will be a bit of beer on top of the yeast.

Generally I'll use a cup of yeast in a brew.
For a lager I'll use all of that.

 

[MrRook]

I don't brew often enough to use a yeast cake, but I don't think I'd use the whole thing unless I was putting a barleywine on top of a bitter.

 

[BeerCat]

If the beer tastes good i will reuse the yeast. If its a lager i might use all the cake or use half to make a 2l starter and pitch 1.5l 24 hours later.

 

[TommyK]

I use it the next day after bottling and just put about 3 tablespoonfuls into a sterilised mug, sealing it with clingfilm to keep bugs out. Next day I do another brew and pitch this into it when it's the right temperature. Fermentation gets going a bit slower than pitching fresh dried yeast though.

I've also saved the dregs from 3 bottles of beer and pitched that into a brew and that has worked too. Useful to know if you've started brewing before you realise you have no yeast in stock!

Thanks. I will try this and do two batches and reuse the yeast cake from the first in the second. I read its a bit slower so to be sure I will make a starter from the cake, add some DME and leave on a stir plate for a day or two.