How many of you have done this with good results? I’m not looking for uber efficiency…I just kinda don’t want to mash in the morning 
I do it all the time works great I also got a increase in efficiency . I preheat my mash tun with same temp of sparge water. So I don’t have a lot of heat lost. But works great for me. If your curious to see how much your mash tun heat lost is test it with hot water for same amount time that you plan on mashing
Sounds great never try this.
Is that just letting an insulated MT sit or using a kettle and putting it in the oven set to warm? I have never tried it either way, just curious.
Yes I just use my mash tun for 5 gallons and if I’m brewing 10 gallons or more I use my 20 gallon Ss brewtech infussion mash tun with the Mtss temp controller and heating pad. It holds temps within one degree. Also it’s amazing on making kettle sours if you like sours. Just set the temp on the controller and leave it alone.
I’ve done it numerous times with success. Definitely expect an increase in efficiency. The wort will be darker in color than with a normal mash and will be more fermentable (beer will finish with a low FG). The overnight mash lends itself to certain beer styles - I’ve been doing it on some Trappist-style beers and can achieve a low FG without the use of sugar. I start my mash a few degrees higher than normal (about 155° as opposed to the normal 150-152°). Then I cover the top of the mash tun with a heating blanket and then cover the entire mash tun with a sleeping bag. Holds the temperature pretty well - less than a 10° drop over 10 hours.
I did this Sunday with a Baltic porter…mashed like I would for an hour…then threw a blanket over it and went to bed…didn’t see an increase in efficiency as it was a big ass grain bill…but I woke up and started boiling Probably do it again with a lower gravity brew.
@uncdeo Do you remember how the baltic porter turned out? I’m considering brewing an Irish stout using the overnight method, but I’m concerned about mashing with dark grains for 8-10 hours. I’m wondering if a long mash will extract too much astringency/harshness from the dark grains. But I’m thinking if my mash ph is in the correct range, then I should be fine.
Do you recall any excessive astringency in the baltic porter?
Just mash the base grains overnight and steep the specialty grains when you brew. They don’t need to be mashed anyway. And especially overnight
Thanks @brew_cat. Now I’m leaning towards mashing the base grains overnight and capping the mash with the roasted grains in the morning prior to lautering.
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You know… I don’t recall any conversations on pH for over night mashing… Does it the length and saturation change the pH for enzymatic benefit ? Or would you still add some medium to get to correct pH? See how a question can leave you wondering? Sneezles61
I would imagine you would adjust your pH as normal
