lager yeast temp shocked?

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dcunitedfan

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Question for the lager brewers out there:

I have had problems with several recent lager batches with fermentation either starting later than normal (I like to see lagers start bubbling about 12 hrs after pitching) or not at all (forcing a quick use of dry yeast). I use single Wyeast Activator packs, no starter, and typically smack the pack about 6 hours before pitching. So the yeast sits at room temp all that time (60s to 70s depending on season) and then goes into wort that's usually in the low 70s at pitch time.

This is where the trouble starts I think - I then put the carboy in a temp controlled freezer and immediately set it for a lager fermentation temperature, say 50F. If I do the trick of taping the temp sensor probe to the carboy, presumably that causes the beer to chill that much faster, and that does seem to align with when I have longer lag times.

I'm wondering if I'm stressing the yeast by changing temps that fast. If I had a better chilling process, I'd chill the wort to 50F before pitching, and then also put the smack pack in a 50F environment between smack and pitch. That presumably would eliminate this problem (if this is what's going on).

Never happens with ales, and of course those ferment at temps closer to what I currently get the wort to before pitching, so there is less temp change.

Has anyone else gone through this, or have any thoughts about whether this is what might be going on?
 
The biggest stressor for the yeast is probably the lack of a starter. I use a HUGE starter for lagers, and usually ferment them at room temperature. I stick it in the fridge and decant the spent wort before warming it slightly and pitching it in my wort. If you're not using a starter, you're underpitching my a very large margin.

I'm a big believer in pitching at fermentation temperatures, the same as ales. I know the instructions say you can pitch at 70, then lower the temperature, but that doesn't seem right to me. I mean, I don't pitch my ales at 85 degrees, then wait for them to come down to 65 degrees. Fermentation would start long before you reached the correct temperature. I like to pitch my 48 degree starter into 50 degree wort. It seems like the slightly warmer wort gets the yeast to work and happy.

If the yeast and the wort and close to the same temperature, then pitching the yeast into room temperature wort isn't an issue. You don't want to pitch fridge temperature yeast into 70 degrees, for example, but pitching a 68 degree starter into 70 degree wort would be fine.
 
I've heard about Jamil's views on using more yeast than a single container, and I've got no reason to disagree, I just haven't tried it yet - I need another part for my DIY stir plate, but that's another story. Good to know that seems to be such an important factor.

So while I can well believe that I'd be better off pitching more yeast in lagers, I was wondering if anyone could confirm if they got better results by first cooling their wort down to the ferment temp before pitching (and presumably keeping the yeast close to pitch temp before pitching), then pitching at a warmer temperature and then cooling the beer post-pitch.
 
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