Hi. I brew using a batch sparge method. I mash in, let it sit an hour, account for absorption and add an "infusion" to heat it up a bit more and bring volume to 1/2 pre-boil volume for 5-10 min. I drain it, then add the other 1/2 pre-boil volume, let it sit 5-10 min, drain, and boil... I wondered if there's any thoughts on doing the mash before work, letting it sit the day, then doing the infusion. I'd make it a thick mash so there'd be more infusion volume. If I mash in at 155 or so and it would sit for about 8 hrs, I have no idea how far the temp would drop... let's say it would drop to 120 or so. Thoughts? Thanks.
I know one person who only does all-night mashes. He lets the mash sit all night long and has never had any problems with that approach, after doing so for decades. However, most literature I have seen recommends against it because of how enzymes work and also because you want to avoid the temperature falling below about 120 F because of bacteria, etc. If you can avoid the temperature dropping that low, theoretically, you shouldn't have any problems. You may wish to read this: http://byo.com/hops/item/931-is-the...mash-overnight-and-just-sparge-in-the-morning
It's going to be a pale ale. I recently had a sour pale ale. It was ok, but not appropriate for the event this beer will be served at. I'll stick with my original method. Thanks.
I've made overnight mash a routine step when doing a high gravity beer. I end up with a more fermentable wort, presumably because, as the temp drops, more sugars get broken down. Or maybe it's just because the enzymes have more time to do their thing. Frankly, I don't care why it works, only that it does. I keep my ten gallon Rubbermaid mash tun in the house during this time with potholders on top for a bit of insulation. I usually see only about a ten degree drop during a typical 8 or 9 hour period. 155F -> 145F seems to work well for me. YMMV.
A 10 degree drop is pretty awesome. I wouldn't mind your system. I use a 40 quart igloo style picnic cooler. I put a double layer of bubble wrap under the lid and wrap it with blankets and hold it closed with the boil pot. I lose 3-5 degrees during the mash, especially this time of year when my basement is chilly (though I brew outside). I often pre-heat the cooler, which helps, but there's still a lot of heat loss. I'm sure the rate of loss would slow over the duration of the mash (rapid loss at first, slowing after an hour or two).
