Yeast too lame?

[sibelman]

Yesterday at about 11AM I made a 2-quart starter with a pouch of Imperial Triple Double, mfg. date: January 14, 2025. I aerated (shook) the still-warm wort in its sanitized gallon jug, added the yeast slurry and swirled. Then I put it in my fermentation chamber at 65°F, and swirled it several times over the course of the next 21 hours. It seemed completely inactive after 12 hours, which surprised me. After 21, it shows only slight activity.

Is it something about this strain? Or is this pouch lame (though handled well) and should be discarded? Or should I simply keep stirring and brew another day?

 

[day_trippr]

Warm it up to ~72°F.

 

[IslandLizard]

When making starters I would keep the temp around 70-75F.
No stir plate?

I aerated (shook) the still-warm wort in its sanitized gallon jug, added the yeast slurry and swirled.

How warm was the wort, and how cold the pack of yeast? Ideally they should be within 10°F when pitching, to prevent temp shock.

a pouch of Imperial Triple Double, mfg. date: January 14, 2025.

That's pretty darn fresh! Viability should be at least 80-85%.
As long as it didn't get accidentally frozen during transport.

 

[sibelman]

When making starters I would keep the temp around 70-75F.
No stir plate?
How warm was the wort, and how cold the pack of yeast? Ideally they should be within 10°F when pitching, to prevent temp shock.


That's pretty darn fresh! Viability should be at least 80-85%.
As long as it didn't get accidentally frozen during transport.

Warm it up to ~72°F.

Thanks for the responses, folks.

No stir plate. The starter wort was way warmer than the yeast pack, probably more like 40°F, so substantial temperature shock occurred. Note: Omega says to let the yeast warm up before pitching. Imperial says pitch cold. But yeast don't know which brand they are.

Too, the Imperial site says of this strain, "Keep an eye on Triple Double, it likes to sit on top of the wort throughout fermentation which may result in a slower than normal fermentation." Maybe not relevant to my little issue, though.

I'll warm up the ferm chamber and brew another day, unless y'all think I should start over and prepare a starter more carefully. Planning a reasonably hefty dubbel, btw. Paying for another yeast pack is not as bad as prejudicing the result.

 

[sibelman]

Thanks again, guys. The dubbel (OG 1.068) I brewed yesterday is happily bubbling away - ferm. chamber at 70°F -after a brief lag phase.