Rescue yeast > 6 months old?

I bought a pack of WY1469 West Yorkshire yeast that was more than 6 months old, hoping I could revive it in a starter. Bad idea. The starter never seemed to start fermenting ("never" meaning overnight in this case) so I gave up and went back to my LHBS for new yeast. But I figured why waste it if I can coddle it back to life, so I poured it into a sanitized nalgene (smelled great as I poured it) but it hasn't cleared after more than 48 hours in the fridge. I can see a layer of yeast at the bottom, but there's a lot of "billowy" sediment floating around throughout the bottle. Is this mostly yeast carcasses? Is it worth decanting and pitching into another starter? What would you guys do? If folks think it will take more than a couple steps to grow a pitchable quantity, I probably won't bother. I'll attach a pic but I'm not sure it'll be so helpful or convincing; the bottle is kind of dark.

Any thoughts? Thanks.

Old yeast will take more than over night to start fermenting. To revive this yeast begin with a 1 liter starter of 1.010 wort. Use the shake and swirl method. This will give you a good visual of when or if fermentation has started.

I have used a number 6+) 6 month or older yeasts. I just pitch a normal starter (2 liter with 200g of DME and a tsp of yeast nutrient) and let it sit on the stir plate for 3-5 days at room temperature (68-ish). Some yeast takes longer some shorter, but I've had 100% success rate in reviving the yeast. They all have gone on to fully ferment their beers.

I believe the stir plate is very helpful, if you do not have one you may be at a disadvantage.


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Your putting it in the fridge before it's done fermenting. Take it out and warm it up and it will finish up. I just made a starter with 7 month old yeast. Took 3 days to ferment out.

A store I frequent sells expired yeast for half off or buy one get one free. I always pick some up and just know that the starter may take a few more days to get going. I usually just use a 1l starter on a stir plate. In fact I am drinking a dubbel right now made with 9 month old 3787.

I just revived some washed yeast that was 11 months old. 1L of 1.040( I realized later that was too much) It took about 36 hours for the yeast to come back to life with intermitten shaking. Right now it is cold crashing in the fridge waiting for a decant and setup and a brew session next week.

I have revived yeast about 13 months old. Just give it time and oxygen.

A little update on this old yeast:

I ended up just buying a different yeast for the beer I intended to be fermented with the 1469.

For the 1469 starter that never started, I ended up cold crashing it, and then I poured off all but ~300 mL of the supernatant. I thought it was interesting that after 9 days in the fridge, there was still a ton of sediment/particulate matter in suspension (and also sedimented layers of trub and yeast). I speculate that this stuff in suspension was mostly dead yeast cells or pieces of cell wall and membrane.

Anyway, after these 9 days in the fridge, the 300 mL starter finally seemed to start fermenting when I left it at room temperature and swirled occasionally, and it seemed to be fermented out after a little more than 48 hours, so I cold-crashed it again.

After decanting the supernatant, I made a 500 mL starter at 1.030; the yeast fermented this one out in about 48 hours. I again cold crashed.

My last step was to decant the supernatant, and add a 1.2 L starter of 1.038 wort to the slurry (around 5 days before a planned brew session). This fermented out in around 24 hours, so I cold crashed it for ~4 days.

On brew day, I decanted all but around 400 mL of the supernatant, let the flask warm to room temperature, and pitched the slurry into a 1.049 pale ale. By day 9, SG was down to 1.011, so it looks like my yeast rescue was a success!

Thanks for all the helpful suggestions!