2 phase brewing

Just wondering if some of these partial mash beers could be done in 2 phases.

Phase 1: Mash specialty grains in one pot and pumpkin(for pumpkin porter) in another. Cool and seal to refrigerate overnight.

Phase 2: Bring all ingredients up to a boil and continue as if all these steps were completed on the same day.

Sometimes I find it hard to block off more than a few hours at a time to brew and unless I'm doing a wheat beer, the specialty grains add time and steps and wondered if some of these could be done the night before after the kids go to sleep so that the rest can be done more efficiently.

So I brewed an extract pumpkin porter that required:
1. Boil pumpkin for 20 mins
2. Then add specialty grains to the pumpkin with some more water and mash for 45 mins.
3. Business as usual

This ended up adding about 1 1/2 hours to my brew time.

Could I have done the first 2 steps the night before, then just added it to the full boil and gone from there the next morning?

I wasn't sure if having the runnings and pumpkin cool down and sit would hurt any chemical reaction needed. My guess it it wouldn't since I'm brewing an extract brew and it'd be like starting from scratch. Maybe just wait and add the pumpkin runnings when I add the extract.

Anyone?

I wouldn't think that would cause an issue. As long as everything was sealed up in a sanitized container. Don't see how that'd been much different than pre-boiling and saving top off water the day before.

You need to bring the wort up to a temperature high enough to kill the lacto bacteria that is on the grain... otherwise the wort will go sour overnight. Bring wort up to like 165- 180* or so for ten(?) min.
look around here for split mash or overnight mash threads for more info.
good luck!

Also, I would carmelize the canned pumpkin for an hour at 350.
It will bring out the sugars and it smells awesome.
you can do this step ahead of time and let it sit overnight.
I do not understand the need (your step) to boil it before the mash but people brew with pumpkin at least 5 diff ways. so it will work out fine.
cheers,
Wendy

You also have to cool the wort quickly or seal it in something airtight before it cools.

Ok. It seems like it might be more work than its worth but I'll hunt for split mash threads for more info