pitching on yeast cake

[normeller]

I am plannning on trying to pitch my next batch directly on the old stout yeast cake for a porter beer. How should I do it? Do I need to clean the krausen from the old fermentation? Do I stir the wort vigorously? Do I use a blow tube?

 

[EoinMag]

You shouldn't do it directly. Swish the cake around and then tip it into a sterilised container of some sort, then wash and sanitise your fermenter thoroughly as usual and then use the mrmalty calculator to work out how much yeast slurry to add back. Never pitch directly onto an old cake, it's unsanitary and it's overpitching.

http://www.mrmalty.com/calc/calc.html

 

[kanzimonson]

+1.

Don't be lazy, pitch proper amounts.

 

[Hammy71]

I don't make a habit of it, but I've done it several times with no ill results. Usually I'm making a 'bigger' beer than before. Rack your beer to keg/bottling bucket and simply add your wort to the fermentor. Everything in the fermentor should be free of bugs. Your beer that was in it wasn't infected so.....

 

[Calder]

And don't forget the blow-off tube, because it is going to take-off like crazy.

 

[EoinMag]

It's lazy practice.

I spend up to 9 hours on a brewday, you want to then go and throw the fruits of that labour into a dirty fermenter?

 

[Yambor44]

This is what happened when I pitched directly onto a yeast cake recently: