Stirring the mash?

[cat007]

Hey all

I'm building my brew rig 2.0 so I can do full 50L batch sizes (currently using a keggle so can only do about 40L batches). My MLT for 2.0 is a 100L pot that's 50cmx50cm - so there's a fair amount of surface area.

I'm building a HERMS rig - so loosing heat through stirring isn't really an issue I'm worried about.

In the big breweries - you see they have mash stirrers that operate throughout the entire mash schedule - but I wonder if this is just because their grain bill is so large they have to stir it so the grains don't settle?

Has anyone experienced using a stirrer for the MLT for big(ish) batches and how has it affected your efficiency?


Cheers
Hunt

 

[treefiddy]

Is the 100 L pot because you want a large surface area/shallow grain bed?

HERMS circulates the liquid past the grain more or less, and areas that don't have good circulation should be lessened in a mash tun such as yours.
By continuous stirring you'd probably only gain a small percent (< $1 worth of grain), which is surely not worth the hassle.

I have the capability to do 50 L batches, and I only use a 50 L keg as a mash tun. It suits me just fine.
If I were to do big beers, I might have a problem.

One way I've thought about getting past the issue of my mash tun being tall and deep is to reverse the flow of my pump.
The liquid would be taken from the top of the tun through a bazooka screen, through the HERMS and back up through the false bottom causing agitation of the mash. When the mash is over, I'd reverse the pump back to normal to form a filter bed.
I haven't tried it yet though, but next time I have cause to put more than 11-12 kg of grain in there I'll have a think about it.

My 2c

 

[cat007]

Hey

Thanks for the reply.
I chose a 100L pot so that I can do big beers and not worry that a 70L pot won't be big enough for 50L strike water plus 18KG of grain - for the DFH 90 minute IPA.

I currently have a 70L chilli bin and often don't have enough room when I do a big beer and need to fly sparge.

Not sure I'll be able to do a reverse flow for my setup.

I guess I'll just have to try it and see.

But you're right - with HERMS the water is constantly being recirculated around through the grain bed so it not having a stirrer might not be a problem....

Cheers
Hunt

 

[Helles]

If you pump from the bottom the grain bed will compact giving the effect of a stiff mash
I do 80lt batches and find I get better efficiency when I stir the mash

 

[Bribie G]

Ever since the invention of steam power and the rise of big breweries they have used "mash rakes" - as well as "underletting" - I guess it works for them. I always stir my BIAB mash when I'm ramping from 63 to 72 then up to mashout to help flush out any sugars that may be hiding in husk material.

However the brother-method of BrauMeister just pumps through the mash from the bottom.

So I'd guess that with our smaller batches it's take it or leave it.

With a larger batch I'd guess stirring might be a benefit. How do those really big "Brew Cafe" style Braumeisters work, do they have a stirrer?

 

[cat007]

I guess it's just a matter of trying it without and see how efficient the rig is. If I'm not hitting the efficiency that I'd like to be - then I guess I could test with some sort of stirrer/mash rake.

Cheers

Hunt

 

[Howlingdog]

BYO article May-June 2010 stirred mash tun

HD