Can I mash the day before I boil?

[thecardiffmonkey]

I've been homebrewing now for about six months, and my standard technique is to mash a couple of pounds of pale malt, some crystal, and speciality grains for 30 minutes at a time at three temperatures (40C, 64C and 70C) and then sparge and start the boil with LME added. However, I am restricted to about three hours (due to work, whining wife etc), so I find I am rushing like mad to finish my brew in time. Does anyone know if its possible for me to mash and sparge my grains in the evening, allow it to cool and then start the boil the next morning? Ive picked up lots of information from this forum, but this is my first post, so please be gentle with me!

[BillyBock]

I see this come up from time to time and some people do it without incident. It doesn't sound like you'd have a large volume of wort--could you refrigerate it? I think your biggest threat is spoiling microbes souring your wort before you get to boil it to kill them.

[brewmeisterintng]

I have read about it but never actually tried it myself. I usually block out a time to brew (6 hours). My wife is very understanding that I have a schedule to keep and while I'm mashing (60 to 90 minutes) I can be at her beckening call but during the sparge and boil she is welcome to visit and chit chat but my focus is directed to the brew. I would search BYO as I belive that is where I read about the guy that would mash late in the evening and sparge/ finish in the morning. Spoilage and wild yeast strains are your only enemy.

-James-

[kandrew54]

I have tried this and it seems to work OK.
I just make sure everything is real well sanatized and cover the Wort as soon as it is finnished. Actually I use a 30L pail with a hole in the lid to collect the wort, and plug the hole with a sterile stopper as soon as it is finnished running.
The "Wizard" on BYO did an article on this and he recomends not keeping it for more than a day or two. I personaly make sure I boil it first thing the next day. I have never tried keeping it longer than about 12-16hrs before boiling.

[cleone]

Its been some time since I tried it, but I had one batch that I collected a couple extra gallons from my mash. I boiled 6 gallons the same day and stored the remainder in my fridge for about week. I essentially used the remainder to create a second mini-batch.

Comparing the main batch and the week-old wort batch, there was little noticeable difference in taste or quality.

I would agree that you need to be careful to fully sanitize everything to avoid off flavors/spoilage, but I can't image storing for a few days being a big problem.

Chris