Evening Mash, Morning Boil?

[Omahawk]

I'm planning to do a partial mash this weekend, and given my schedule for this weekend would love to split it into two phases: an evening mash and a morning boil. I'm guessing about 7 hours in between.

The concern with the overnight break wouldn't be infection, since it will be boiling in the morning for my extract and hops additions. Are there issues with this break? I know mash temps affect the sugars.

Any experience/advice is appreciated.

[Mylo]

I'm planning to do a partial mash this weekend, and given my schedule for this weekend would love to split it into two phases: an evening mash and a morning boil. I'm guessing about 7 hours in between.

The concern with the overnight break wouldn't be infection, since it will be boiling in the morning for my extract and hops additions. Are there issues with this break? I know mash temps affect the sugars.

Any experience/advice is appreciated.

I would imagine that your wort would be a little tart and funky by the morning. Lactobacillus occurs naturally on grain. Unless you boil it for 10 minutes or so before going to bed - they are going to start to take hold (and perhaps other funky stuff, too). Sure you'll kill them when you eventually boil - but they will have started to sour the wort by then - and you won't be able to get rid of that funk.

Just bite the bullet and stay up to finish the brew. Or make a Berliner Weiss.... your choice.


Mylo

[bluelou6]

I once ran out of propane about 15 minutes into the boil. It was to late to get more, so I put a lid on the kettle and finished the boil in the morning. The beer turned out fine. I agree with Mylo that you would need to do at least a short boil.

[Elbone]

I once ran out of propane about 15 minutes into the boil. It was to late to get more, so I put a lid on the kettle and finished the boil in the morning. The beer turned out fine. I agree with Mylo that you would need to do at least a short boil.

I think sourness would only be a problem if the mash fell below 140F or so for a long time. If you could maintain your mash temp, say 154F for the entire 7 hours, I think you'd be OK. How to do this, I don't know. Maybe mash in a pot in a very low oven?

EDIT: OK, I found a study that looked at temperature and death times for lactobacillus cultures found in Swiss cheese. The lactobacillus on grain may be different but are probably pretty similar. The vast majority of cultures were killed off within 10 minutes at 150F. All were killed off within an hour at that temp. If you can hold the mash temp, you'd be effectively performing a very-low-temperature pasteurization as far as lactobacillus is concerned. I have no idea what else might grow but you would kill it in the boil whatever it was.

[Omahawk]

Thanks for the advice, folks. I started wondering about a 5-10 minute boil after the mash, then chilling it prior to refrigerating overnight. It should chill quickly, as I'll only be mashing / sparging about 4 lbs of grain for about 1.5 - 2 gallons of wort at the end, prior to morning hop and extract additions. Maintaining 150ish degrees overnight sounds like it's beyond the capabilities of my simple equipment (other than throwing it in the oven at 175, my lowest setting).

I'll probably just wake up early tomorrow and knock it out in a single session.