Expired yeast...Ok to use?

[Morrey]

I have a smack pack of Wyeast Hefe yeast mfg in Jan '17. It is roughly 2 months past their suggested 6 mos vitality date. Yeast calculators suggest at 8 months it has 22% vitality and a two step starter is suggested.

I often like to under-pitch my Hefe's so the yeast throws the flavors I like in this style. Leading me to the two questions I have:

Is this yeast still ok to try? If the smack pack swells some I can assume the yeast is at least semi-ok?

Is it feasible that I do a one step starter (not two steps) to boost my cell count and still be a shade under pitched? If this was a fresh smack pack, I usually let it swell and pitch direct, no starter at all.

I've never let a yeast get this far away from me before and I hate to just toss it if I can salvage a decent beer with it.

Thanks!!

 

[dyqik]

It depends on how it was stored and transported. Some yeast calculators significantly underestimate viability for yeast that's had a good cold-chain storage, IMO. If you don't know, do a starter after smacking, and see how it goes.

A fairly small starter should restrict the growth sufficiently that you don't have much risk of overpitching.

 

[Morrey]

It depends on how it was stored and transported. Some yeast calculators significantly underestimate viability for yeast that's had a good cold-chain storage, IMO. If you don't know, do a starter after smacking, and see how it goes.

A fairly small starter should restrict the growth sufficiently that you don't have much risk of overpitching.

I can't say the conditions it was shipped to the LHBS, but it was dead winter when I bought it and the yeast was less than a month old. This is a high volume warehouse so they get large volumes of yeast in often....so I might risk assuming the yeast was packaged properly to the seller. I stored it in the bottom drawer in a spare fridge I keep all my hops (freezer) and yeast in, so I keep it cold and it gets opened less often than most refrigerators.

Would I be able to sort of judge the vitality of the yeast once I activate the smack pack by how swollen the bag becomes? Is this a "safe" indicator of whether I actually need to do a starter at all?

 

[dyqik]

I can't say the conditions it was shipped to the LHBS, but it was dead winter when I bought it and the yeast was less than a month old. This is a high volume warehouse so they get large volumes of yeast in often....so I might risk assuming the yeast was packaged properly to the seller. I stored it in the bottom drawer in a spare fridge I keep all my hops (freezer) and yeast in, so I keep it cold and it gets opened less often than most refrigerators.

That sounds pretty safe as an assumption.

Would I be able to sort of judge the vitality of the yeast once I activate the smack pack by how swollen the bag becomes? Is this a "safe" indicator of whether I actually need to do a starter at all?

Maybe. I think the rate of swelling might be a reasonable test, but you need to take account of temperature there as well. If it swells quickly, then, yeah, the yeast is happily active. But you'd need to be ready to pitch it right then, I think, to get the advantage of the yeast being active. Which doesn't allow time for a starter if it doesn't work.

I guess I'd do a small starter 48 hours in advance, so that you get some growth and activity, with some time to brew if the yeast get through the starter quickly.

 

[Morrey]

But you'd need to be ready to pitch it right then, I think, to get the advantage of the yeast being active. Which doesn't allow time for a starter if it doesn't work.

I guess I'd do a small starter 48 hours in advance, so that you get some growth and activity, with some time to brew if the yeast get through the starter quickly.

I had considered that if the smack pack swelled I could pitch it as is. But what if it didn't and I need it right then with wort sitting there ready? Up the creek so to speak.

As you are helping me work thru this, a small starter two days out shall be my plan. It can't possibly hurt, but it can certainly help. Good idea.

 

[dyqik]

The other option would be to have a packet of Danstar Munich Classic (not Danstar Munich) on standby. I've made a good hefe with that, and it'll keep in the freezer until the next batch if you don't need it.

 

[madscientist451]

I've used lots of out dated yeast, My LHBS will give it away if you ask after you buy something. Sometimes it works, sometimes not, so I'll make a starter, then brew a small experimental batch and toss it in. I've had decent results except for a Brett strain that didn't do anything.
Its a cheap way to try different yeasts. I'd say go for it, but have some dry yeast or another lager yeast re-pitch on hand in case you have issues.

 

[catdaddy66]

I once bought a half dozen different yeast strains that were out of date. I used one or two within a couple of weeks but one I didn't use for almost 6 months.

Made a two step starter with each and had zero issues with fermentation, even from the oldest of the bunch. I think you will be fine with a single or double step starter.