2nd generation saison yeast (Wyeast 3724)
 

I brewed up a rye saison in April, bottled it in June. Came out great. I washed and saved the yeast, because I want to use it again but then I got to thinking, it might not be in the best shape...

The beer had a 1.066 OG and a 1.010 FG. So that's 1) a starting gravity that was a bit on the high side and 2) 85% attenuation. The only reason I'm not sure about using it again is beacuse I recentlly made a wheat brown porter with a 2nd generation Wyeast 1313 and it pooped out quick. 1.053 OG and it's sitting at 1.018 after 2 weeks.

Thoughts? Should I ditch the yeast? or step it up with a nice slow starter and use it again?

3724 will work great on subsequent pitches (even from the 1.066 OG), but you've waited much too long, even if stored cold for the past 4 months. It could be 10% viable or less at this point. You could do a starter and wash the dead cells out again but that is a lot of handling. Better to use it within 2 weeks next time.

Really? Shoot. I was under the impression that washed yeast can last up to 10 months in the fridge. At least that's what I read in the big giant yeast washing thread. I haven't put the theory to practice...the oldest saved yeast I've used was about 2 months or so.

Regardless, I went to the LHBS at lunch. Thought I should cover my bases. Bought a vial of WLP585 Saison III and a vial of Brett C. Gonna be a yummy saison.

There might be some salvageable cells left, but after 10 months in the fridge it's going to be mostly dead. 10 months in the freezer if properly stored would be reasonable. If you have time you might be able to build it back up, but the chances of an infection are pretty high. After a month in the fridge the viability drops to 50%. If I don't use a yeast that has been in the fridge for a month I'll make up a starter just to wash it again.

If that is the case, how come beersmith will say that a 3 month old vial of White Labs yeast is stil 50% viable? Does handling and packaging make that big of a difference?

I think you should make a starter, and step it up. People make successful batches from old bottle yeast, and year-old washed yeast. It's not ideal, and viability will certainly be low, but for a funky Belgian yeast, I say go for it.

Oh, and you're first batch was probably not finished. 1.010 sounds high for 3724. If you give it time, it will drop it well into the 1.00Xs.

Man, I'll tell you, what a fickle yeast! I gave it 2 and a half months, in a temp controlled environment, and it still crept along at a snail's pace. I guess I could have squeezed another 2 points out of it, but it wasn't worth waiting another month or two.

I'll say this, 3724 makes a hell of a beer. This one came out fairly dry for the FG, and people frickin' love it. It's just sloooooow.

Wyeast is way better at packaging yeast than we are, thankfully. This data is taken from Mr.Malty, you can see how much faster re-used slurry dies off.

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