Using older wyeast smack packs toss it or just try

got couple of old w yeast smack packs before i do toss them out
the viabilty close to zero procent now question ?
just toss it out, or i did some calculation using yeast calculator got to use 153 grams of dme to get it back to life . now i am concerned using this , if i use two pack of w yeast it does say it meets the requirments for a one liter starter ??? at a abv of1.055
for a five gal batch

What are the production dates on the smack packs? The per cent viability estimated depends upon which calculator you are using. There are some calculators which do not calculate viability too well.

In my experience it is never worth the risk of losing a batch if the yeast is more than about 8 or 9 months old. Toss it and buy new yeast.

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feb 28

The Brew United calculator has the viability at 33%. I would use it for my beer. May take a two step starter.

I regularly use yeast that’s almost a year old, and well past its use-by date. But as @flars said, you definitely need to make a starter, and preferably a multiple-stage starter, if you use yeast that’s out of date. Most importantly to make sure there’s some viable yeast in there, and also to build up a large enough cell count to attenuate the batch. So I’d absolutely use it, just make a starter well ahead of time.

If I make a starter and don’t end up using it right away, I’ll just put an airlock on the jug and let it rest at cool temperatures until I’m ready to use it. If it sits for over a month, just give it some fresh wort a few days before you use it, then pitch away.

Oh, Feb 28 isn’t too bad. Just make a starter and it should be alright.

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Me always make a starter.

Let me use this kind of calculator

Kind of strange so much difference between brewers friend yeast calculator. And the brew united calculator

BF and Mrmalty use an interpolated linear equation for reduced of yeast viability. The calculators have not used cell counts. This isn’t the greatest wording but both severely under estimate viability.

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Yes but they never took into consideration the affect of a left handed Fetzer valve. :confused: Think I would make a starter.

I would start with a smaller ABV starter 1.025, just to wake up what yeast is left, then yer next one you can ramp up the ABV to start it multiplying, 1.040…. Sneezles61

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I don’t know what your time is worth, but for the $6 or $7 it costs to buy a new pack VS the 4 hours it takes to brew a good batch of beer and toss in a questionable yeast, I would lean towards buying a new pack.

Wilco lives on an island out in the middle of the ocean, and gittin supplies is a rather time consuming process. I know he has to account for all he gits. I see yer new to the site and may not have seen when he first came a board… Sneezles61

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did place new order and should get new yeast next saturday ariving by delta airlines
but still got some packs of yeast in my fridge indeed me on a island so got to use my supply as long as it last
do make a starter and do a grav reading if it does not work toss it out got lots of dry yeast to back me up but do like the smack packs or kveik yeast

HAHA gotcha! Yeah I suppose that would be problematic. That would explain a lot about your question assuming your not pulling my leg about this island thing. Haha

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hahaa no i do live on a island cald bonaire
beer supply big issue do buy for about 6 to 8 months supply about one month before the end place a new order shipping time between 10 to 20 days yeast from w yeast or yeast bay fedex or friends bring it down