Waiting for Wort to come UP to pitching temp

I brewed a simple American Wheat today.

7lbs Wheat LME
1lb 20L Crystal
1oz Cascade at 60min
.5oz Cascade at 15min

I've been reading about various ways to cool the Wort as quickly as possible without using a Wort chiller. The technique I chose today is EXTREMELY EFFECTIVE. So Effective that flame out was at noon and my wort is still 42 degrees 7:30pm

What did I do? I froze two gallons of spring water from the store and cut the bottle off the ice and put the ice chunks in the fermenter and poured the wort over the ice, thinking the ice would melt quickly. Not so much...

Why did I choose this idea? I read several accounts of this technique and it made sense. I also watched Jim Koch do it in "The art of home brewing" at Samuel Adams website

I went ahead and put the lid on the fermenter with the air lock in place as soon as I realized it was going to be a while.

With the fermenter sealed should I worry about not being able to pitch the yeast until tomorrow?

Thanks,
AL

In the future, just get the water down to near freezing, but not quite ice. I'd put about 1 gallon back into the pot and bring it to a boil, then chuck that back into the fermenter and stir it up.

Nah, as long as it's sealed up you're fine. I wouldn't bother taking it out to heat it and putting it back in and all that effort. You can just pitch the next day. I do it all the time when I have to pitch in the winter.

This makes me wonder, is there any downside to simply pitching the yeast at 42 degrees? if it's liquid yeast, it's around that temp already, and it's got to warm up to ~70 either way. The only difference is if it warms up in the vial/smackpack or in the wort. Obviously the ferment will be slow to start, but the overall time from flameout to active fermemtation would be about the same either way, becuase the key factor is the delay for the wort to warm up to ~70 degrees.

I read in a post last year regarding Wyeast's Fat Tire ale yeast that someone at New Belguim had said that they pitch that yeast into their Fat Tire wort at 50 degrees and let it slowly rise to about 70, and that this gives them a cleaner ferment. I tried it myself and had good results (sadly the yeast I harvested from that batch was left at my old home when I moved)