Just washed my first yeast yesterday and I was wondering what different techniques are used here in the BA community. I have done some research, watched quirky guys on youtube, read articles, etc. I just would like some input on what everyone thinks. The process I used is as follows: Pre-boiled and cooled 2qts water, sanitized 1 gal glass jug, 2 1qt mason jars and their rings and lids. Transferred beer as I normally would, kept the lid on my 6.5 gal bucket as much as possible while siphoning. When siphon was done, I added the 2 qt water and shook vigorously for ~1min, let sit for ~1hr. I then poured out contents carefully through a funnel into 1gal glass jug leaving as much of the trub as possible(I was able to fill jug just over halfway), put the sanitized lid on jug and put jug into fridge for1 hr. After an hour passed, I then carefully poured off the clear layer left on the top and some of the cloudy layer(I realize yeast is in this layer but I only had 2 1qt mason jars to use). I did not see much trub in the jug so I just mixed the remainder of the jug to evenly distribute the yeast though the liquid and then filled each of my mason jars. I did this so I would end up with the same amount of yeast in each jar. So then I put on the sanitized lids and into the fridge they went. Any tips on technique? How long is my yeast good for? (it is wlp001 California ale)
I think letting the yeast/water sit for an hour is a bit excessive. I usually pre boil a gallon or 1.5 gallons and add that after siphoning. Let it sit for 10-15 minutes. Then add that to a sterilized 2l erlenmyer. Then ill either throw that flask in the fridge to drop the yeast out or pour (wash) that into another smaller 1l container if its a hoppy beer to get the cleanest yeast possible. Once the yeast is dropped out (2 or 3 days in fridge) ill decant most of the spent beer water, swirl into solution and put into a sterilized 125 or 250 ml erlenmyer. Little erlenmyers are awesome for yeast storage because their so easy to sterilize.
I find that if you let the carboy sit to "settle" for too long, it actually gets harder to separate the yeast from the trub. The trub usually settles out quickly (15-25 minutes) and you want the yeast to stay "in suspension" so that when you decant the liquid off of the trub, the yeast is in it! From what I've read, you should be able to pitch your yeast (1 mason jar w/o a starter) for the next 2 weeks. After that long, you will want to make a starter with it prior to pitching. I've also read that washed yeast stored in water in a refrigerator dies much more quickly (can be as low as 50% viability after 1 month I believe) so don't wash yeast in hopes of long term storage if you will be storing them in water filled mason jars. I believe Mr. Malty puts the viability for yeast SLURRY (despite the fact that it assumes only about 25% of the slurry is yeast) at about 10% after 2 months FWIW....
Here is the best tutorial I've seen on yeast washing and this is what I do: http://billybrew.com/yeast-washing I boil/wash with one gallon and end up 5-6 pint mason jars. Once complete and in the fridge, I wait at least two weeks to consolidate the jars. It varies, but usually have 20ml of slurry in each jar. I estimate 2 bilion cells/ml but know this is rough. I would budget a 21% loss per month, same as store-bought yeast. If anyone has better estimates, please post.
^^^THIS on the billybrew link. I know guys who cap bottles full of trub with great success. The shelf life for them is 5 months with a stir plate. (I think they have better chances of rejuvenating yeast with a stir plate but I can't vouch for that as I don't own one). So long as you make attempts to stanitize your equpment and any water that you add you're in good shape. If you use tap water make sure campden tablets enter the equation.
Here's another good yeast washing tutorial. https://home.comcast.net/~wnevits/wizards/yeast_washing_rev_5.pdf
Thanks to The Most Interesting Man In The World! I did review Mr. Malty and their calculator has the 50% monthly "death rate" you described. So I need to adjust my assumptions when making starters. For the OP: My house yeast is the Chico/California strain you refer to. I use it roughly every other brew session, or about once each 6 weeks. It is easy to re-start and if you use the calculator referred to by TMIMITW you can build it up to the desired range. I have a strain currently fermenting on it's fourth cycle and all seems well.
So it sounds like I just need to decrease my rest time in the fermenter then so I'm sure to get the yeast still in suspension and the yeast will be good for much longer than I'll need to store it for. I do have a stir plate so that's not a problem. Thanks all, I appreciate all the input and advice.
I add another 500ml to each starter, then save that in a quart mason jar. I will also put a pint mason jar filled about 2/3 full with boiling water in the fridge at the same time. When the boiled water is cooled, I decant most liquid from the saved starter then add it to my jar of distilled water. I prefer saving my yeast from starters as there is not as much to separate out, and I am saving it at the same time as pitching which seems much easier to me. Also, a second washing can be done, but I have not yet seen the need with this process. My homebrew club has a yeast bank, and I am enjoying the use of Conan and Pacman yeast lately...which I plan to keep both around for a while.
Last month I found a few 1/2 pint jars of wlp001 dated Feb '12 in the back of my fridge. I decided to give it a try for the hell of it and brewed up an ipa (og: 1.071). I made a 1l starter & lag time was about 8-9 hours. I don't have another beer to compare side by side for the yeast character, but I'm very happy with the final result.
Single starter, but thinking back, I misspoke a little. I made a 2l starter (2c dme 8c water) and split that into 2 growlers. I split my wort into two 2.5 gal batches to utilize different hops. Each batch got 1l of yeast from the growler. I'm hoping the "off flavors" from this batch carry over when I re-wash the yeast. I think It'll be great in a late season watermelon wheat.
