The Friday Conundrum: Copper Chain Agitated Mash Tun?

[mr_wibble]

Greetings Earthlings ...

While on a brewery tour in Munich (October 2012), I took a photo inside a mash-tun at the Paulaner micro brewery.
It was all dark inside, but upon viewing my photo, I could see some *stuff* in the bottom.



To me it looks like those blades, joined with a copper chain rotate in the bottom of the tank.

But is it?

And Why?

Looks like it needs a bit of a clean too.

cheers,
-kt

 

[geneabovill]

Looks like its attached to that clear tube at one end. Possibly it weighs it down/let's the brewer raise it. Or possible stainless steel isn't blingy over ther, and copper is the in thing.

 

[yardy]

It's not clear tube, it's stainless flat bar with a pitch rolled into it and the radius on the outer end makes it look like tube.

I'd say the round bar wasn't getting the desired effect so they've added the flat bar with the pitch to either force the mash up or down depending on which direction it's rotated, the chain was probably added by a fitter.

 

[bradsbrew]

the chain was probably added by a fitter.

:lol:

 

[stux]

wouldn't they also use the same thing to push the spent grain out for disposal by reversing the direction?

 

[Bribie G]

Looks like mash tun rakes have to have chains for some obscure reason. Maybe it's a Goth thing.

 

[wessmith]

This is a traditional German "Mash/Kettle". The three round tubes are stays holding the rotating shaft welded to the shell of the tank, the impellers or blades do the stirring. The chain (stainless steel, not copper but covered in beer stone) looks like having been added to increase agitation and mixing directly above the heated bottom of the kettle. These systems also double as a kettle so the steam jacket is designed to go to a full boil and would probably have struggled to keep to a 1C temp rise when mashing - hence the chain stirrer to keep the temp even.

Wes

 

[wessmith]

Looks like mash tun rakes have to have chains for some obscure reason. Maybe it's a Goth thing.

View attachment 59888

Bribie, that is a lauter tun, not a mash tun. The chains pull the blades into the "plough" position when reversed to eject the spent grist.

Wes

 

[Bribie G]

So that's why my lauter tun was so slow.

 

[wessmith]

So that's why my lauter tun was so slow.

Mate, methinks your are still in Goth mode.....

Wes

 

[kelbygreen]

maybe its to stop grain laying on the bottom and scorching as the blades are above the bottom a bit. Not sure how its heated but if its underneath you dont want the grain just laying there

 

[Maheel]

would you want the chain to be copper so it does not damage the pot as much as a stainless chain would

a "sacrificial" type chain

 

[justsomeguy]

would you want the chain to be copper so it does not damage the pot as much as a stainless chain would

a "sacrificial" type chain

Would have to agree there.

I've got a book somewhere that shows a similar system used in the UK in the 1800's. I think it was for mash stirring.

I'd have thought that it was to prevent grain sticking to the bottom of the mash tun, let's say, if you were doing direct fired step mash.

Regards,
justsomeguy

 

[RdeVjun]

That pair of ugly black marks on the flat surface (i.e. base) wouldn't be from direct heating, would they? If it has a steam jacket then probably not, they will be something else.

 

[Thirsty Boy]

I've seen pictures of chain attached to stirrers before..... cant remember the source material though. Older belgian brewing systems maybe?? I seem to recall that it was mostly used in direct fired mash/kettles, or kettles with bottom steam jackets only, not for stirring the mash per sel but for during the boil. Rakes rotate during the boil, causing the chains to scrape constantly on the bottom of the kettle, which stops protein etc buliding up on the hot surface and reducing thermal transfer efficiency, or potentially scorching. Makes the kettle more energy efficient and also means CIPs dont have to done as often or as intensley.

 

[wessmith]

Hi TB, these Paulaner setups all use Caspary systems. They are not so old really although I note the Munich Paulaner is closed at the moment for an update. They are usually a 2 vessel system - mash/kettle and lauter. Those chains are very traditional but I reckon they are there in the Caspary systems to move the grist below the higher mounted impellor. Newer designs have a different base profile with the impellor VERY close to the bottom.

Wes