I just racked to secondary an ale using S-05 yeast. I was wondering if anyone reuses dry yeast slurry? Dry yeast is relatively cheap but is it feasible to save and reuse it? Maybe once or twice? Thanks.
There are many pro breweries that pitch dry yeast and then repitch multiple times.
Brewery around here repitches dry yeast (05 as far as I know) 5 generations, and their beers are all very big, 10% abv and higher, which is really hard on yeast. Once or twice? Sure! You might read up on “yeast rinsing” (NOT washing) to get good yeast and not dead stuff to repitch.
I’ve given thought to what I would do in the future if I decided to repitch. At home brew volume any way. I would pull a 100ml sample at high krausen and add it to a 1L oxygenated starter. Cover with foil and let it grow and flock. Store it in a fridge, decant and pitch to an active starter on brew day.
I rinse and repitch because I not only don’t buy yeast, but I only do a starter a couple of times a year. And I know the rinsed yeast is fresher than a pack shipped from Wyeast, if I use it within a shirt time from harvesting. Cuz I don’t live in their backyard. I also have always wondered, would a starter like you describe count as a generation? Anywho I rinse and repitch because I’m cheap, lazy, and it works. And I still am convinced yeast need a few gens to adapt to your brewery environment and hit peak performance. That said, my way works best if you have a “house yeast” you stick with.
Thanks for the replies. I have good luck with s-05 and next time I’ll save and reuse.
I have a slurry that’s got to be 15 plus batches old. Grab a sanitized mason jar right after racking and scoop it up. This and wyeast American ale are my “house strains”
I have reused US-05 slurry many times. I have never had any problems.
A somewhat cleaner and easier way to do it is to make an over-sized starter, keep part of it and pitch the rest. The next time you again grow an over-sized starter from the stuff you kept, keep part again and pitch the rest. This is what people do when making sourdough bread.
True I do that with sourdough. But I don’t actually think this is easier: you have to make a starter every time, it’s easier just to dump the slurry in a jar and rinse it before reusing! And I’ll repeat, IME it takes a yeast culture several generations to adapt to brewing conditions instead of lab or starter conditions. By repitching slurry, you will get better performance. There seems to be some consensus that 3 to 5 generations is the magic point of adaptation, but YMMV. BTW, the famous Poilâne sourdoughs in Paris are actually made not with a separate starter, but by moving forward a portion of each batch of dough, a new batch every four hours, which has been going on for many many decades! Now that’s "repitching! "
I make a starter every time, so making a bigger starter is no extra work and there is no rinsing involved. Which one is easier depends on your process. I wanted to throw it out there as an alternative which may work better for some people.
You don’t really need or want a starter with dry yeast though. In fact you could be doing more harm than good by doing a starter with dry yeast. Dry yeast is in a more stable state due to its packaging and the glycogen reserves will not be depleted as with liquid yeast. If you make a starter with dry yeast make sure you make a really big one (5+ gallons 11.5 gram pack) or only use a quarter of the pack or you will be causing the cells to use their glycogen reserves but then not have enough media to re-store.
So rather than making a 5 gallon starter with dry yeast, just throw the yeast you need into the fermentor (or for best results hydrate the yeast first) and just harvest afterward.
As just an interesting aside, I always go back to the time I found out that Chimay actually grows a fresh culture for each batch and does not repitch. I always found that interesting.
I get what you are saying though.
I could be wrong, but I don’t think he was talking about a dry yeast starter, but rather his SOP of making a starter for every batch.
^^^^
Yeah, Chimay uses a fresh lab culture for every batch, and Brooklyn has continuously repitched without reculturing since Garret Oliver took over in January '96. Most breweries probably are somewhere in the middle! I start fresh mostly when a hiatus prevents me from repitching promptly.
Re-pitching is fine, as long as sanitation is maintained. The best way to do that is to schedule brew days in conjunction with racking-from-primary fermenter days…plus with re-pitches, I always use some yeast nutrient in the re-pitching (typically added to the wort at 10 minutes left in the boil.
I took a lager out to 25 generations with no ill-effects, but anymore with the convenience of dry yeast, I typically don’t re-pitch all that often.
Cheers!
I could be wrong, but I don’t think he was talking about a dry yeast starter, but rather his SOP of making a starter for every batch.
I couldn’t tell for sure but since the thread is about dry yeast I’d put that out there.
You’re right. I should have said that I make a starter for every batch except on the rare occasion when I use dry yeast. I had forgotten that the original topic was specific to dry yeast (or dry the first time around, before harvesting).

You’re right. I should have said that I make a starter for every batch except on the rare occasion when I use dry yeast. I had forgotten that the original topic was specific to dry yeast (or dry the first time around, before harvesting).
That makes more sense! haha!