Liquid Yeast Viability After 5 Months?

[ozpowell]

Hi Guys,

I have an pack of Wy 3944 which is coming on 5 months since manufacture. I received it approx 2 weeks after manufacture and placed it straight in the fridge (~3C). Just plugged the mfg date into Jamil's pitching calculator (link) and it's telling me that I'm sitting on a viability of only 10%!!! Can anyone confirm whether or not you expect that to be accurate given the storage conditons? I don't really feel like building a 6 or 7L starter .

 

[Stuster]

I'd say it'll be fine to use. I have recently used a few older wyeast packs (6 months out of date or so) and they worked absolutely fine. You'll probably find it takes a little longer for the pack to puff up but other than that there didn't seem much difference to me. Personally, I'd just build up a small starter, then prop it up to a normal sized starter and go for it.

 

[newguy]

I've used several smack packs that were 2+ years old. The oldest I've ever used was the wyeast sweet mead yeast - that was 5 or 6 years old at the time. Smack it. It will swell, but it won't swell as quickly as a fresh pack. Regardless of the pack's age, a starter is a good idea but I haven't had any issues with old packs and pitching my normal sized starter of ~1 - 1.5l for 2 x 21l carboys. You're fine. Just smack it and build up your normal starter and it will be fine.

 

[Hargie]

....make a 1.5-2 ltr starter, aerate , it'll be fine...


...if it makes you feel any better i recently scored a 2nd place with a CAP that i brewed with wyeast 2007...

...it was 14 months old when i smacked it...full attenuation, no diacetyl, no acetaldehyde, etc etc....

 

[Cortez The Killer]

I smacked a 2112 Cal Lager from Jan 07 last Tuesday

and the pack was fit to burst by Monday this week when I added it to a starter

Just under a week isn't too bad for an almost 18 month old yeast

Cheers

 

[ozpowell]

So, I smacked it and, after 48 hours the package was fully swollen. I've now got it on the stir-plate with a 250 ml 1040 starter. I'll build it up to 1L tomorrow. Thanks for the advice guys! Brewing a Wit tomorrow

 

[therook]

Quick question, when you guys build your starters up do you make a one off lets say 2 litres of wort and add bit by bit? until you have built it up to your desired starter size over a period of time.

Hope this makes sense

Rook

 

[drsmurto]

It depends on how much yeast you have to start with.

If its an activator pack then pitch it straight into whatever starter size you need.

With propagator packs i tend to go 2L first and then double it if i need a larger volume.

And if you have bugger all yeast then several steps....

 

[therook]

It depends on how much yeast you have to start with.

If its an activator pack then pitch it straight into whatever starter size you need.

With propagator packs i tend to go 2L first and then double it if i need a larger volume.

And if you have bugger all yeast then several steps....

Dr,

If you have bugger all yeast....what i am asking is do you make a one off wort and just keep topping up to the desired level after each stage has fermented out.

Rook

 

[Cortez The Killer]

As long as you can keep it sterile while waiting for each step - eg keep it in the fridge

I usually make up each starter step in a succeeding erlenmeyer flask sizes - boil it and add previous starter to it when cool enough

Either way

Cheers

 

[drsmurto]

As long as you can keep it sterile while waiting for each step - eg keep it in the fridge

I usually make up each starter step in a succeeding erlenmeyer flask sizes - boil it and add previous starter to it when cool enough

Either way

Cheers

Thats pretty much what i do except i chill and pour of the beer each time. Step up from 100mL. 500mL, 2L etc

Sorry Rook, am in need of my arvo coffee, caffeine levels have dropped to dangerously low.....