Brew in a bag, overnight mash for high efficiency

I am sure this has been mentioned before, but it merits repeating. Brew-in-a-bag done with an overnight mash - in my case, a 3 gallon batch of small batch - gets consistently huge efficiency. Today was a real surprise. I aimed for 1.062 and ended with 1.078.

I am hoping to get better at prediction as I do it more, but I keep getting thrown by higher and higher efficiency.

At what percentage efficiency can I expect to top out?

BIAB w/overnight mashing, no-chill cooling, etc. BIAB is so simple a cave-man can do it!

To what temp was ur Bag at first at ?

Cheers!

Huge efficiency is not a number... what do you call huge (actual brew house efficiency)?

My actual efficiency was around 86% and my temp was 156 to start, placed into a per-heated oven at 170 (my lowest).

Every batch gets more efficient, too. The first time was something like 60%. I'm on my seventh batch, now, and it keeps getting higher. I'm not actually trying to make high abv beer, so I'm curious where I'll predict my upper limit.

badducky said:

My actual efficiency was around 86% and my temp was 156 to start, placed into a per-heated oven at 170 (my lowest).

Every batch gets more efficient, too. The first time was something like 60%. I'm on my seventh batch, now, and it keeps getting higher. I'm not actually trying to make high abv beer, so I'm curious where I'll predict my upper limit.

Click to expand...

let me get this straight...you just drop the bag in mash water preheated to arrive at whatever mash temps you want, then shut up in an insulated enviroment stove, cooler or large styrene box for 8-12 hours? afterward drain bag and boil liquor as usual?

GD

Are you increasing the rest time also ?

From what I've read. Over extraction by high temps/oversoaking can cause unwanted properties in your batch, like haze for instance.

I might be wrong tho. Im just a newbie but I think Ive heard it of Dr Bamworth @ Brewing Networks podcast about hazes.

Anyways. Cheers. If your improving your efficiency with similar rest times then your improving your methods!

That's the process, gd. I take it two or three degrees hotter than target to start just because of the long mash.

I haven't had haze problems with most batches, particularly lately as I've done this more.

The thing about the long mash is timing. I don't have unlimited time to brew, and it's easier for me to divide it up before an off morning to do some of the stuff at night after work. I wake up and get the rest done over breakfast and I'm...

Hey, speaking of which, I have to go back to work! Cheers!

increased time really shouldn't show much change in efficiency unless you're getting poor enzymatic activity from poor crush/mix/pH, especially at the higher temp end. once conversion is done, more time wouldnt increase efficiency.

are you seeing an equal increase in your attenuation, cuz that is more time dependant?

I heard of people getting their beers a little bit drier with the overnight mash. It sounds like a good idea though seeing how easy brew in a bag is. I was doing it before I had a mash tun and I loved it. It would be great for my smaller batches.

Dcp and deuce hit the nail on the head. overnight will increase the number of short chain sugars even after the conversion from starch to sugar is completed before the 1 hour mark.

For mash theory see here:
http://woodlandbrew.blogspot.com/2013/01/mash-temperature-theory.html

BIAB efficiency is all about volume of run off vs volume tied up in grain absorption.