Harvested Yeast - Still Good?

[LJvermonster]

Good day folks!
I brewed a batch back in May 2021 and harvested the Conan yeast. Visually to me it doesn't look good but does anyone have experience with using harvested yeast after a year? It was stored in a fridge for the last year.

I don't like the black color film on the top.

Thoughts appreciated!

 

[odie]

sniff test. If it smells bad toss it. If nothing bad, give it a try.

 

[Spivey24]

Not worth the risk of losing a batch over.

 

[GoodTruble]

I keep several jars of yeast the same way in a fridge, but if it gets that dark layer, I toss it. Like Spivey24 said, not worth losing a batch over.

If you really want to find out, just do 1 gallon of light dme wort and use a small portion of the yeast. If that turns out okay, use the yeast cake to make your full batch.

 

[LJvermonster]

I keep several jars of yeast the same way in a fridge, but if it gets that dark layer, I toss it. Like Spivey24 said, not worth losing a batch over.

If you really want to find out, just do 1 gallon of light dme wort and use a small portion of the yeast. If that turns out okay, use the yeast cake to make your full batch.

Ha, this feedback is good enough for me! Time to toss!

 

[hottpeper13]

Can't explain why but when I switched to covering mine with a double layer of foil the black never shows up. It's weird but true. Also only under beer never water.

 

[LJvermonster]

Can't explain why but when I switched to covering mine with a double layer of foil the black never shows up. It's weird but true. Also only under beer never water.

How long would you keep your yeast? The black doesn’t show up until month 8ish of storage.

 

[hottpeper13]

In September of 2021 I brought back to life a saison strain from September 2018. That is the longest,but most of my ranched yeast gose 6-8 months between refreshing. These are all from overbulit starters so they never fermented a beer,don't know if that makes a difference or not.

 

[seatazzz]

Here's my two cents; yeast packets (dry) or smack packs (liquid) are a hell of a lot cheaper than what grain & hops for a batch can cost. If in doubt, toss it out. Those photos look nasty. I've never had that happen to my harvested yeast, but I rarely use it if it's beyond 2 months. I'd rather not take the risk. On the other hand, if it's all you've got, do what was suggested above and build a starter from it, and see how that smells/tastes (the beer on top of it, anyway). If it's good, use it.