Hello my fellow brewer mates,
I’m a young brewer just learning the ropes of the game. I have been using a fresh vial of yeast for each fermentation but now am considering the option of re using my yeast. Could you please educate me on the do’s and dont’s plus the procedure which I should be following???
Thanks a lot
Just Google “yeast washing” and you’ll find plenty of info. Here’s a couple…
http://www.donosborn.com/homebrew/yeast_washing_the_wyeast_way.htm
I don’t personally feel you need to wash the yeast as long as you are only using it 3-4 gens. All you have to do is recover the yeast in a measurable container, such as a Mason Jar with ml markings on the side. Then use the yeast pitching calc. at www.mrmalty.com to get an idea how much yeast you need to pitch.
While you are there, note what size starter you will need for a vial or smack pack. Even though WL and WY sell their vials/packs as “pitchable”, if you are not making a starter you are underpitching and not making the best beer possible.
Frankly, after a few tries, I stopped washing yeast. I didn’t find it provided any appreciable benefit for the effort. Now I simply divide the yeast slurry between 2 sanitized containers and store it on the fridge til I’m ready to use it.
How long will washed yeast last in the fridge between brews?
I also stopped rinsing yeast as I think the benefit isn’t there for the effort and the risk of contamination inherent in all of that handling. Because I brew a wide variety and I don’t keep the yeast very long, I rarely get past 4 generations. 2-3 is common. I also do not get hops or hot break in the fermenter. Maybe that matters and maybe it doesn’t but it’s my personal situation either way.
My rule is to repitch the yeast within 3 weeks of the end of fermentation (not the harvest date). My ideal is harvesting and pitching on the same day around a week or week and a half after the end of fermentation (2 weeks from brewday for ales, 3 for lagers).
I’ve reused unwashed yeast as long as 5 months after storage.
What kind of cell count per unit of volume do you assume when pitching slurry?
+1
Note: glass jars with tightly closed lids could prove dangerous. Tupperware types much safer (I believe Denny uses this). My preference is slurry divided up between sanitized PET bottles (plastic soda or water bottles).
Not Tupperware per se, but plastic containers with snap on lids. If pressure builds, the lids bulge and will eventually pop open. WAY better than exploding glass!
If you’re doing back-to-back brews, you can simply transfer your wort right on top of the yeast cake from the last batch. I’ve done this many times. No need for storage.
Typically, you’ll want to move from lighter to darker/bigger beers if you do this, but not everyone necessarily follows that order.
I get more consistent results by pitching only part of the slurry. Its by far better to pitch the right amount of yeast. Overpitching can cause problems, just like underpitching. Plus, you are multiplying the amount of dead yeast every time which can cause anything from head retention problems to autolysis off flavors.