Mash now, boil later?

[Fire-Brew]

My question is in regard to mashing/sparging, then setting the wort in a sanitized/sealed container, with the intent of doing the boil a few hours later. There seems to be a fair amount of information out there in regard to mashing at night, and then boiling the next morning, but I am interested in a shorter time frame.

Has anyone here done this?
If so, did you find your results to be as if you had done it immediately, or did you find a difference in your finished product?

Thanks in advance!

 

[BigJay13]

I have not done it but I wouldn't think a few hours is long enough to make it spoil.

 

[Bamsdealer]

Don't even worry about putting it in a sanitized sealed container. The bugs are already in there, you just want to start your boil before they have a chance to create off flavors. Just collect your runnings in your kettle, put the lid on and you should be fine for a few hours.

 

[IslandLizard]

Last brew I had a left-over pint of wort from sparging and let it sit in a pot. When I was cleaning up, a few hours later, it was still fine, but the next morning (6-8 hours later) it had a haze on it, and smelled like a mash tun that's been sitting for a day.

So there's a short window where that wort appears to be safe. As with most (bio)chemical processes, heat exponentially increases the reaction speed. And hot wort is a perfect stadium.

So I would keep it as short as possible and if you feel you need more time, bring the wort up to or near boiling temps to pasteurize. But then once you're there, you may as well finish it.

Also letting hot wort sit may increase fermentability, as the enzymes have more time to chew the larger sugar chains. This may or may not be desired. A good mash out will prevent some of that.

 

[Fire-Brew]

I appreciate the responses. It does seem as though it is a sooner-the-better type scenario, which makes sense. This would not be a regular process for me, especially since I typically do a brew, set-up to clean-up, in about 4.5 hrs. However, this weekend may present itself with this needing to happen.

BigJay, I have read that some people let it rest overnight, even when they are not targeting a sour brew. I have not attempted this method (mash Fri night & brew Sat morning), but it sounds like it works for some. I suppose like any wort though, getting it cooled down quickly ought to retard some of the unwanted growth.

 

[TBBrewer]

I recently did a overnight mash on a hefe. I got higher than expected extraction and attenuation. I left the mash for about 7hrs. There was no off flavors and it turned out to be a good brew. When I woke to brew, I was at 135F. I wrapped my mash tun with a sleeping bag. Go for it, it makes the brew day about half as long. Got up at 8am and was cleaned up and finished by 11.