Old Washed Yeast - worth trying?

[imtrashed]

I have an inch or two of washed Kolsch yeast in a 2 qt jar that was washed from a batch I brewed in April 2012. It was a lot of yeast, but it has been in in the fridge since then (over 18 months). Think it's worth trying to use in a starter and a batch of beer next weekend? Should I just buy some new yeast, make a starter and go with that?

 

[ColoHox]

By using the old yeast in a starter, you will probably end up pitching a lot of dead or lysed cells, along with the new cells you have grown. I always default to using the healthiest yeast possible, when in doubt.

 

[stpug]

I wouldn't use it as-is, however I would try to build back up a healthy colony. This could very well take a week or more though.

-Basically a teaspoon of the washed yeast from the "middle" layer into 200ml 1.025ish starter wort. Stir plate until it looks good (2-5 days).
-Add to 750ml 1.030ish starter wort (nutrients and oxygenated). Should be done in 24-48 hours.
-Crash cool for 1-2 days
-Decant all top water
-Pitch yeast into 1.6L 1.035ish starter wort (nutrients and oxygen would be good here too). Should be done in 24-36 hours.

Yeast is ready for a new batch (after a proper taste and smell test).

I did this with an antwerp ale yeast I had sitting in the fridge for about 12 months. Opened it up and it smelled a lot like braunschweiger (i.e. liverwurst); lysed yeast. I did the process above and after a good 7-10 days of building it back up it smelled and tasted like normal brewers yeast. I was getting very quick starters and good krausen too.

 

[imtrashed]

I wouldn't use it as-is, however I would try to build back up a healthy colony. This could very well take a week or more though.

-Basically a teaspoon of the washed yeast from the "middle" layer into 200ml 1.025ish starter wort. Stir plate until it looks good (2-5 days).
-Add to 750ml 1.030ish starter wort (nutrients and oxygenated). Should be done in 24-48 hours.
-Crash cool for 1-2 days
-Decant all top water
-Pitch yeast into 1.6L 1.035ish starter wort (nutrients and oxygen would be good here too). Should be done in 24-36 hours.

Yeast is ready for a new batch (after a proper taste and smell test).

I did this with an antwerp ale yeast I had sitting in the fridge for about 12 months. Opened it up and it smelled a lot like braunschweiger (i.e. liverwurst); lysed yeast. I did the process above and after a good 7-10 days of building it back up it smelled and tasted like normal brewers yeast. I was getting very quick starters and good krausen too.

Thanks. This is kind of what I was thinking, but on the other hand, I'm now wondering if it's all worth it to save $7. Might just buy another vial/pack and get that into a starter. If it was some type of yeast that I couldn't currently get (Platinum or Private collection or something I harvested), then I might try to salvage it, but I think I might junk it and start fresh.

I moved and took a hiatus from brewing for a bit, so I have a bunch of jars with 12-18 month-old yeast. I'm thinking I should just start washing and saving all new stuff and toss what I have.

 

[wilserbrewer]

While it is certainly possible to build up a culture from yeast that is 1 1/2 years old, you will never really know how contaminated it might be. Might work fine, might not ??? Really up to you if the $7 is worth it?

 

[dinnerstick]

While it is certainly possible to build up a culture from yeast that is 1 1/2 years old, you will never really know how contaminated it might be. Might work fine, might not ??? Really up to you if the $7 is worth it?

this!
if you are going to plate it out and re-start from a single clean colony then maybe, but that's not worth the effort when you can buy it, and starting blind from some of the slurry... it's not worth the risk against $7 price tag for new culture, imo!

 

[stpug]

You guys are so boring (jokingly)

I'm always up for a challenge, but I can certainly understand the "risk" factor. There's no harm in going through the reviving process with the old yeast just to see how well it responds. I guess I find fun in a challenge.

I have planned a reviving event on some old scottish ale yeast that was harvest from a 9% ABV beer, poorly washed, reused on an amber, and then set in the fridge for a year or more. I'll just have to plan a low ABV cream ale with it or something in case things don't work out perfectly