Pitched warm yeast starter into cold wort. Advice?

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Aug 12, 2010
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I brewed a German Pilsner yesterday. 10 Gallons at 1.059 OG (first brew on a new rig and overboiled a tad). So my OG is higher than desirable. I made a 5L starter of WLP830. However, after decanting, the yeast cake on the bottom of my flask was really thick and stuck to the bottom. So I chilled some of my wort to ambient temperature and added it to the flask to wake up my yeast. I'd say ambient was about 60F yesterday.

My concern is about the delta in temperature between my ambient starter and pitching temperature. I chilled my worth down to 46F, pitched the starter + 1 extra pack of WLP 830. I aerated with pure O2 for ~45 seconds, and then again 2 hours after pitching for 60 seconds. I then let the wort free rise up to 50F and have been holding it there.

I've been reading about how pitching warm yeast slurry into cold wort can put the yeast to sleep. How concerned should I be about this? How long should I wait for signs of activity before being concerned?

If remediation is needed, what do you recommend? I'd like to avoid letting my wort rise too much higher in temperature, the max I'd like to go is 52F. I ferment in a stainless conical, so I could blow some CO2 into the bottom cone to rouse the yeast, or even stick a sanitized spoon in to give it a stir.

Any and all advice is appreciated :)