Overnight Mashing ?

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I've mashed overnight in my grainfather. The idea was to set the mash off on a Friday evening so that I can have a shorter brewday on the Saturday (kids, etc). A typical schedule might be:

50C for 30 mins (or however long before I remember to go back)
64C overnight
76C for 15 mins

Since working from home, I've tended to prep the water on a Thursday night and delay heating until the morning so I can mash in quickly when I wake up. Have a cuppa, sort the kids out, move to the next mash step which I hold for the whole day. When I'm ready to brew, I then mash out whilst heating the sparge water.

Efficiency has been great with all styles.

If you don't have a grainfather, using an inkbird to control the mash could work although it won't be quite so accurate.
Do you recirculate the entire mash?
 
Yes you do. Just like normal.

My only difference is that I hold at 20c overnight (recirc) and then the mash program step starts in early hours.
 
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I have a friend who I introduced the overnight mash. Now he starts the mash about 8 pm. He gets up about 5 am and sets the lauter/sparge and then goes back to bed. By the time he gets up at a reasonable hour, it's ready to boil. It saves him time and he gets a better brewhouse efficiency.
 
Yup. I enjoy my first coffee and lift the malt out. Sooooo nice.

I have an gen 1 bm20 so I only have 5 program steps so.
1. 20°c for 180mins
2. 20°c for 180mins
3. 20°c for 180mins
4. 50°c for 60mins
5. 65°c for 60 mins

With temp uplifts, this is a 12 hour program, so I press start in the evening at the time I want to boil. Easy to remember.

I usually dough in when I get a minute teatime ish. Then nip out at 7.30 pm press start. Next morning at 7.30 am boil is waiting, pop the malt pipe out, start the boil, get some breakfast, hop, drink more tea... And I am done by 9am when I remove the boiling lid, replace it with the standard lid, slip the insulation and run away.

Happy days.
 
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One of us seems to be confused. The overnight mash should be at mash temp. You should be running about 66 to 68 overnight, followed by a mash-out temp of 77 for 10 min.

What positive action do you suppose is happening to the grist at 20 degrees for 9 hours? There is certainly no diastatic enzyme activity at that temp.
 
I think it is family time that makes people overnight mash so as to free up some time or they get ear ache from SWMBO
 
Ha ha. Pretty sure we all enjoy the end product. It's the faffing around and all the other shyte that can sometimes get you down.
Exactly my point. Thread after thread of ways to make the process hands free, quicker and less of chore. Like saying you enjoy hiking, then get helicopter dropped onto Scarfell pike for the view. The end product can be easily bought.
 
One of us seems to be confused. The overnight mash should be at mash temp. You should be running about 66 to 68 overnight, followed by a mash-out temp of 77 for 10 min.

What positive action do you suppose is happening to the grist at 20 degrees for 9 hours? There is certainly no diastatic enzyme activity at that temp.
Here's what he told me ...

"Hey, Peebee, that CC Mike is on the forum. This'll confuse him".

Despicable i'n'he! I'm blowing the whistle on him 'cos I know, he knows, I don't know what that 50C step is for. That's to wind me up, not you, Grrr.
 
Lol.

I popped it in special like for you Peebee. Just to see if you would notice.

OK...OK... Its a protein rest. Which should be pointless.
 
One of us seems to be confused.


So Peebee said

"But I don't really "over-night mash"; and neither does anyone else ... really! The mashing enzymes just can't keep going that long at that heat."


And I said..
" Absolutely. This is "cold holding and then an early morning mash". But to be fair that's a lot to type when you bang on about it as much as I do 🤣🤣"

And then Mike said..

" What positive action do you suppose is happening to the grist at 20 degrees for 9 hours? "

So I said..

" I am getting a bloody good night's sleep. That's what"

So then someone else pipes up and says...

"I'm convinced there's a lot of people that don't actually enjoy brewing."

"So" I says.
"do you pay a mechanic £500 to service your car and then hold his hand he's doing it? Eh do you? Don't think so. I also didn't buy a lawnmower and cut the grass with my teeth. But I do like a drive and looking at my nice garden"


So you see there is no confusion here.... Don't park your car on the grass! Easy innit.
 
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I simply related how my friend does it.
My method is a step mash started late in the afternoon. Once the mash is up to the saccharification temp, I move it into an insulated chest and leave it overnight (8 - 10 hrs.) I got the idea from an interrupted brew session. I then remembered that Dave Line wrote about it in one of his books.
I've been brewing like this for the last 18 years.
 
You beat me to it, I was going to mention Dave Line.

I started with this, because it is (imo) time, energy & kit efficient.

A better description of my entire process might be "grain to bottle"
 
I simply related how my friend does it.
My method is a step mash started late in the afternoon. Once the mash is up to the saccharification temp, I move it into an insulated chest and leave it overnight (8 - 10 hrs.) I got the idea from an interrupted brew session. I then remembered that Dave Line wrote about it in one of his books.
I've been brewing like this for the last 18 years.
Is that the same Mike as getting it upto your mash temp then wrapping overnight (duvet blankets etc)which is what I used to do. I do not do this as often now as time is not as much at a premium but thats how I did it
 
Do you recirculate the entire mash?

Yeah, although I've given up on the overnight mash. Thanks to COVID leading to more working from home, I now brew on a Friday, starting the mash at lunchtime and then moving onto sparge at about 8 once the kids are in bed. Can normally be done by 10, having had two hours of blues and brews on my own.
 
All sounds like too much hassle to me , with the added danger of inducing vomit aromas from lacto if your insulation isn't up to it. But for those that dont work from home I can appreciate it's a big plus

Personally I put my water on at 8am when the wife leaves for work, have a coffee and then put the mash on before I start work at 9
Give it a stir in my morning coffee break and then pull the malt at lunch.
Whilst the wort is heating up for the boil I will do a sparge (if needed) and go and eat my lunch.
Boil should have started before I need to go back to work and I add my bittering hops. Quick 5 min break to add aroma hops and drop my cooling coil at the right time and then turn off the heat and jobs jobbed till I finish work and pour it in to my fermenter
 
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