Wyeast smack packs
Wyeast smack packs
How long are these packs good for. I bought 2 kits earlier this year and only made one kit. The pack has been refrigerated for the entire time. It was manufactured Nov of 2010. Is it still good? It's a Kolsch yeast.
good/bad is not a well defined descriptor for this. As yeast ages without sugars to eat cells die. so it is usually represented in a percentage that represents the living cells remaining.
Being that old, you are probably down somewhere in the 20% range I would think for viable cells still in there. you should be able to revive it for brewing however, what you should do is smack it and give it a 3 - 5 days to swell, it will not swell as quickly as normal as there are fewer living cells in there then if it were say a month old. So after it does swell. Then do a couple of starters to build the cell count up again. You can do like a 500ML starter, then chill and pour off the wort. Then pour into a 1 Liter starter and let that finish. That should give you a good cell count for brewing. Also make sure you oxygenate or airate your starters to promote yeast growth instead of conversion action.
Being that old, you are probably down somewhere in the 20% range I would think for viable cells still in there. you should be able to revive it for brewing however, what you should do is smack it and give it a 3 - 5 days to swell, it will not swell as quickly as normal as there are fewer living cells in there then if it were say a month old. So after it does swell. Then do a couple of starters to build the cell count up again. You can do like a 500ML starter, then chill and pour off the wort. Then pour into a 1 Liter starter and let that finish. That should give you a good cell count for brewing. Also make sure you oxygenate or airate your starters to promote yeast growth instead of conversion action.
If you've never done a starter before, just ask for help. Most of the members generally use them, especially for higher gravity beers. It's not hard, but as with any thing else, there are some tricks. For example, if you're trying to revive an older yeast pack like this, adding some yeast nutrient to the starter wort is a good idea.
A Mighty Wind's A Brewing
“Life is short - break the rules, forgive quickly, kiss slowly, love truly, laugh uncontrollably, and never regret anything that made you smile” ― Mae West
“Life is short - break the rules, forgive quickly, kiss slowly, love truly, laugh uncontrollably, and never regret anything that made you smile” ― Mae West