I've heard it happening, but never experienced - until NOW!

Brewed a 5gal batch of NWIPA Saturday morning. Didn't do a starter but after wort was cooled to pitching temp (67deg), I pitched two WLP013 PurePitch packs into the well aerated 1.060 wort and put the air lock on.

Bumped the temp to 68 late yesterday afternoon. Going on 36hrs since pitching and NOTHING!!

What gives.

 

Patience, my good man. Patience...

 

By God fermentation has started - albiet very slowly. Still dont get the dynamics here. What makes this different from the rest of the 75+ brews I've done.

 

74 of them started fermenting quicker.

 

Alright, who let Captain Obvious back on the forum?

 

My guess is that there is a small leak in your fermenter setup and CO2 is escaping from somewhere instead of bubbling through your airlock. Check your bucket lid / carboy stopper / hose barb.

 

I seem to remember that during the interview with Dave Logsdon of Wyeast on the Basic Brewing Radio Podcast, Dave suggested pitching at a higher temperature than your final fermentation temp. 67 degrees is great for an ale to ferment at, but I think he suggested pitching at closer 70-75, then letting in naturally drop. Don't take my word for it though. Listen to the interview.

 

If you got both pouches of yeast at the same time from the same place, it is not unrealistic for both of them to have been subject to environmental conditions that "stunned" the yeast. Could have accidentally been frozen, overheated and damaged, just old, who knows.

 

Sounds like the lack of a yeast starter is the outlier here -- even with the double yeast packs, this doesn't necessarily make up for yeast that's already in action