Did you know you can reuse yeast from a previous batch of beer? I sure did. That nasty pile of yellow orange cheese looking growth at the bottom of your fermenter is actually a massive culture of viable yeast. You can actual pour a new batch of cooled wort right on top of it if you wanted, though its up for debate if that is good practice or not. Another option is called “Yeast Washing” which is literally washing the yeast from the bottle of the fermenter into sanitized jars for future use.
I harvested Pacman yeast from a bottle of Rogue Breweries Sig’s Northwestern Ale which was used in my Gold Dragon Ale. I really did not want to go through the trouble of buying another bottles and trying to grow the yeast from it again, especially when I had a huge yeast cake sitting at the bottom of my Gold Dragon Ale. I moved that all to the secondary fermenter to gain access to the yeast cake at the bottom.
To wash yeast is simple.
1) Wash and sanatize several jars or one large jar
2) Boil up a few liters of water (enough to fill all the jars)
3) Pour the boiled water into the jars, cover them and place them into the fridge
4) Once cooled, pour this water onto the yeast cake, stir and siphon off the yellow sludge back into the jars.
5) Place these jars full of ‘washed yeast’ into the fridge to allow them to settle.
And here is the final product. When I am ready to use it I will remove it from the fridge and allow it to warm to room temperature. I will then decant as much of the clearish top liquid from it, pour some cooled wort into the jar and within a few hours I should have a starter!
Washed Pacman yeast ready for my next brew!