Old yeast worked - Anyone else used old yeast successfully?

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Calder

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I brewed for the first time in 9 months today. Making a brew with my Homegrown hops harvested last week.

Normally I brew every month and have fresh yeast or fresh slurry to use. But because I had not brewed for a long time I didn't have any fresh yeast. I found several old packs of yeast in the fridge, and thought I would use one of them; worst case, I run out tomorrow and get a fresh pack to pitch.

I had several to choose from. I decided on a pack of Safebrew T-58, with a Best By date of 5/2010 (12+ years old). Hydrated in water at 84 F for 30 minutes, and then added to wort (6 gallons). After 3.5 hours, had an inch of krausen and bubbles coming out the blow-off tube. Too early to tell what the final result will be, but it is alive!

Looks like I got lucky. Would be interested if anyone knows of potential issues I may have with having used such old yeast.

The other choices I had were Nottingham (Best by 9/2011), Windsor (BB 11/2011), Safeale S-04 (5/2011), and Mangrove Jack's M27 (BB 2/2016). Without realizing it, I used the oldest. I normally use liquid yeast, these were bought as back-ups that I never needed.

Anyone else have a tale of using old yeast. Would be nice to know if I just got real lucky, or if dry yeast stays viable (for a decade) when stored in the fridge.
 
Dried yeast has a half-life of a decade or more - you won't have had as many cells as a fresh pack but T-58 is a beast so it's less critical.

I've made bread with dry baking yeast that was 20 years old, it rose but only by about half as much as a fresh pack.
 
I actually just tried baking with a bread yeast which expired a year ago (closed single sachet) and it didn't really work anymore. It was really slow although I used already twice the recommended amount of yeast per amount of flour.

It eventually rose a little bit, but the majority of it must have been dead.
 
If I use dry yeast that is up to about 4 years old, I pitch at a normal rate. Older than that, it's still good but I pitch double the amount. Nice advantage of dry yeast is that it lasts soooo long in the refrigerator, you never need to worry about viability. Not like with liquid yeast which is nearly 100% dead after 8-9 months.
 
We normally brew once or twice a month, using the harvested slurry from a prior brew. If the slurry is 2 or 3 weeks old, it will kick off right away, with little lag time.

Just brewed a Festbier, using W-2124 that was 3 months old. It was slow to get going, so added some Diamond that was only a couple weeks old. The ferment took off immediately after adding the Diamond slurry.

Dry yeast has a long shelf life if kept cold. Liquid yeast, not so much.

Regarding the Festbier, this is the first time 2 different yeast strains have been used in a single beer.
 
Liquid yeast is often viable well after the manufacturer's expiration date. it is probably useful to make a starter before brew day to ensure that viability. But on more than one occasion I've had those starters blow the top off the flask. be
 
I used to own a homebrew store in the early 2000s. I would occasionaly find packs of Wyeast that fell to the back of the big fridge I had at the time and got buried someplace. For fun I would smack them. The oldest one I ever found was over 3 years old, almost 4. It took a long time but it finally swelled up after maybe 3 weeks. Don’t remember what strain it was. I have used several that were over a year old.
 
I actually just tried baking with a bread yeast which expired a year ago (closed single sachet) and it didn't really work anymore. It was really slow although I used already twice the recommended amount of yeast per amount of flour.

It eventually rose a little bit, but the majority of it must have been dead.

I've had store bought bread yeast last for well over a year but I've also had different brands die off in the same time. The yeast that died quicker forewarned of a shorter expiration on the package. That's probably the first time I've actually had yeast die shortly after the stated expiration date. I got the dough to rise about half as much as well, which might have just been a product of the yeast in the flour.
 
"Revived" a few packs of Omega Hothead that were kept cold a year past their expiration date. Did a stepped starter and saved some of the yeast for future batches. Ended up building it back up around 6-8 months later from a jar in the fridge and fermented with it again and froze some of the overbuilt starter. Been using this culture sparingly for 3 years or so now. Either Kveik is a beast or yeast is just that resilient in general or both :)
 
I normally harvest yeast from a helles and repitch it into a bock. This time I did a split batch of 5 gallons each helles fermented with the Ayinger yeast strain from white labs and the (supposedly) Augustiner strain from Omega. I decided to grab the yeast from the Omega strain and then left it in the fridge for three weeks before I could brew the bock and it was dead. I've never had that happen before.
 
Most of the pitch recommendations are to over pitch. So your older yeast maybe had less viable cells, maybe not significant... but resulted in a pitch of the correct amount.

I'm not certain with even the freshest of dry yeast packs that I can tell any difference from using one or double the amount of yeast from one batch to the next.
 
The question was mainly about dry yeasts, and from people's experience, is a 'well kept' 12 years old yeast an OK thing to pitch. Would/Could one pitch the pack and be reasonably confident it will work, or was my experience a rarity. Looks like 1 person had similar experience. Not seen any replies saying their experience was negative.

I know yeasts keep 'forever'. I have samples of liquid yeasts that are several years old, and I have no doubt that I can build a colony to eventually pitch, but I certainly would not straight pitch them into a full batch because there will not be enough viable cells to ensure fermentation takes place ahead of any infection taking hold of the brew.

Dry yeast will eventually reach the point where there are not enough live cells to get the brew going quick enough to hold infection at bay. My experience (sample of 1) is that after 12 years in the fridge, the yeast is still good enough to brew with. As I mentioned, this was not a gamble or risk on my part. I would have just gone out and bought new yeast and pitched it the next day if I have not seen any signs of life. It just happened to be all I had on hand at the time.
 
Yeah expiration dates arent really a thing, ive revived a 2 year old pack of 3068 and it took about 5 or 6 days to wake up but then it took off. I have a pack of hothead that i dont really want but might just multiply and give away to some people around here.
 
About a year ago I cultured the dregs from a particularly good 12% ABV wild fermented beer that I brewed over a year prior. All I did was pitch the dregs into a mason jar of wort and it was fermenting beautifully in a couple of days. A few weeks later I pitched the starter into a 1.030 wort and it fermented down to 1.000 in about 3 weeks + another 3 weeks for bottle conditioning. It tasted like a saison with some citrusy notes and no detectable off flavors. If wild yeast was able to remain viable for over a year in a 12% ABV moderately hopped beer, I’m guessing even liquid yeast can be revived for quite a while past the expiration date.
 
I have a satchet of Mangrove Jacks bavarian lager that has a best before date of 10/2020. I want to use it for a 1.058 Oktoberfest this weekend. should I make a starter with it? I don't think I can get another pack by then. Any thoughts?
 
I have a satchet of Mangrove Jacks bavarian lager that has a best before date of 10/2020. I want to use it for a 1.058 Oktoberfest this weekend. should I make a starter with it? I don't think I can get another pack by then. Any thoughts?
It will probably be just fine. Maybe consider rehydrating if you don't normally do that, or brew only 3 gallons instead of 5 or 6. These are a couple of ideas that will guarantee success. But I still think you'll be fine with one pack.
 
I have a satchet of Mangrove Jacks bavarian lager that has a best before date of 10/2020. I want to use it for a 1.058 Oktoberfest this weekend. should I make a starter with it? I don't think I can get another pack by then. Any thoughts?
You would need two pack packs anyway, even with fresh packs.
 
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