Pitching onto yeast cake.

[Bheher]

In past batches I have racked a beer off of a yeast cake and pitched a new batch on top of that yeast. In my frementer right now is a Scottish 60 Schilling and I am brewing a Scottish Strong that wil ferment on the yest cake.
60 shilling has been in there for 10 days and finished fermenting a couple days ago. My question is how long can I let it sit on that yeast and still reuse the yeast? Is 17 days too long?

 

[S0meB0dy]

17 days is fine. Yeast can sit for months in packets on store shelves and work fine so a few days in the fermenter won't hurt it.

 

[whoneedsabeer]

Should be ok...

http://dsc.discovery.com/news/2008/09/23/ancient-yeast-beer.html

 

[pericles]

17 days is fine.

 

[Pick]

I've got a keg fermentor that I had done a hefe in about 4 months ago. It has about a gallon or less of beer sitting on the yeast cake. Could I repitch on this or should I wash it first?

 

[daugenet]

I've got a keg fermentor that I had done a hefe in about 4 months ago. It has about a gallon or less of beer sitting on the yeast cake. Could I repitch on this or should I wash it first?

If its in the keg you could always use some co2 to push the yeast out and into the new container (and avoid the beer)

4 months might be a bit much though. it could be fine also. only one way to find out for sure....