Is my yeast too old?

[chicago_beers]

Hi guys. I've got a good size yeast cake at the bottom of my primary fermenting bucket, and I'd like to re-use it. There's one problem- I transferred the wort into the secondary about a month ago. There's about 1/8 inch of wort on top of the cake, and the bucket is still stacked with CO2. The airtight lid and airlock has been on it since I transferred the wort out. The racking cane was carefully sanitized. Do you think it's still good to pitch on top of??

[Billy Klubb]

what temp has it been sitting at? I'd probably dump it if it's been warm. but I don't like to chance it.

[chicago_beers]

It's been at 66% for about a month.

[brewinhard]

Definitely don't use it. Buckets are notorious for being permeable to oxygen and speeding up the aging process. At 66 degrees that yeast is not something you are going to want to brew with. Time to go get some fresh yeast and make some killer beer!