How long does yeast keep?

[blackntan65]

I had planned to get back into brewing 5 years ago and stocked up on hops and yeast. But, my motivation fizzled out and I only did one batch. So, I still have an assortment of dry yeast packages and pellet hops that I kept in the freezer all this time. Would I be making a mistake by trying to use either the hops or the yeast? I just hate to waste anything.

 

[barrog]

Chances are good that your dry yeast is still useable. Other people here have used old yeast with no problem although you may still want to get some new yeast just as a backup. Your hops on the other hand are most likely junk and unlike old yeast, old hops will ruin a whole batch. Just my 2 cents. Good luck

 

[boo boo]

I think 5 years would be pushing it. Do you want a chance of ruining a batch to save a few dollars worth of yeast and hops?

 

[BrewerBear]

You could make a starter with the yeast to see if it is still any good,if not toss some of it in the last 5 minutes of the boil.

 

[dnslater]

The hops might also be a reason for concern.

 

[monkeybox]

The hops might also be a reason for concern.

You may be able to sell them as "aged hops" to a lambic brewer.

 

[BradleyBrew]

The yeast is questionable... i would make a starter. I tried to use 2 year old hops and the flavor and aroma was just not there. I would chalk them up to a loss and move on with some fresh hops.

 

[Calder]

If kept undisturbed in the freezer for 5 years, both the hops and yeast will be OK.

Use about 2 to 3 times the amount of hops you might normally use as they will have lost a lot of their oils. Pellets will keep better than leaf. You can find calculators that will estimate the oil loss.

In a fridge, dry yeast looses about 4% viability a year. In a freezer, it will be less than that.

If you want a lot of hop aroma, you probably want to get some fresh finishing hops.

 

[BradleyBrew]

mr. malty puts dry yeast at 2+ years old at 50% viability.

 

[Calder]

mr. malty puts dry yeast at 2+ years old at 50% viability.

And it says that yeast slurry is only 10% viable after 2 months. I've had no problems straight pitching slurry after 6 months (not what I would normally do).

Mr. Malty is not the bible, and is generally way wrong in yeast viability calculations.


However, to counter your comment; in 'Yeast', (written by Jamil, who also put together the Mr. Malty calculator), page 160, shelf life of dry yeast, "Stored under typical refrigeration temperatures of 38 F it only loses about 4% of its viability per year"

 

[BradleyBrew]

Never stated it was the holy grail of yeast calculations lol.. Just a resource. Regardless in dealing with yeast that is a 1/2 decade old I would still make a starter just to ensure viability.

 

[blackntan65]

Thanks for all the feedback. Sounds like the yeast may be usable as long as I use a starter. I may try an small batch with the hops as an experiment. It's blazing hot here on the Central Coast so I can't even think about brewing right now. But, I will report back on the yeast and/or hops experiment in case anyone is curious.