Saving Yeast Question

Hey guys.. i was thinking about saving my yeast from my blue moon clone that is currently in primary. I was thinking of racking to secondary tomorrow.. seeing everything is going to plan. The whole idea of saving yeast ive been curious of and read some forum posts as well as internet sites.. but im still kind of confused.
From what i gather i would place the slurry into either a mason jar or beer bottle and put in fridge / freezer, let sit and pour off the first layer to get to the middle layer. IF this is true how do you get rid of the bottom layer to just the middle.. or is this not needed. Also do you have to add some sort of concoction into the slurry like yo would a starter? If you guys could help me out i would appreciate it! thanks much!

- MF -

This is what I do: first of all, I plan my racking days to fall really close to the brewing days. When I rack from the primary I leave the yeast on the bottom of the fermenter, then pour it into a mason jar, cap it and stick it in the fridge. I take it out an hour later and decant the liquid, then cap it again and leave it in the fridge till brew day (usually a day or two away). When I have my wort chilled and aerated I take the jar out, open it, decant as much left over liquid as I can, swirlt the jar to suspend the yeast and pitch the whole slurry into the wort.
There you go, simple, easy and works really well!

The thing that had me messed up on this was I didn't understand what the layers were. When it is separated the top layer should be water and beer. You can get rid of that. Below that should be cloudy water and beer. The cloudiness is yeast suspended in the water and beer. Keep the cloudy stuff. Below that should be a thin layer of yeast. Of course you want to keep that. The bottom layer should be yucky trub. Get rid if that crap.

Check out the Wyeast website, they have excellent instructions for washing yeast. There is also some good info on the wiki.

Thanks guys!.your information is much appreciated . one more question though.. say i was to keep this in the fridge for a while.. would i need an air lock? or would just keeping the lid of the mason jar on work fine?

I would seal it with the lid, as long as the beer has fermented completely you should have no problems. However, an airlock would work as well.

If it is washed you should put a lid on the jar, no fermentation should be occurring if washed properly.