One For The Mash Stirrers

[geoff_tewierik]

In theory, stirring the mash a couple of times during the mashing process should increase the enzymatic activity, i.e. the enzymes are moved around to areas within the mash where sugars are still present that they can work on.

I'm looking for some ideas that I may be able to apply to my own system to assist me in getting a more controlled mash process.

How do you go about stirring your mash during the mashing process?

How do you maintain the temperature of your mash when you give it a stir?

Cheers,

GT

*edit for stupid spaces caused by cut and paste.

 

[Quintrex]

If you really want to, I'd recirculate with a pump. I'm not so sure that agitation during the mash will help efficiency
(I'd generally only agitate/stir if you are doing multiple infusion mashing).

 

[mxd]

I think you'll find various threads about stiring etc.. From what I have read (my understanding) is a HERMS or RIMS will give you the same affect ? (continuous recirculation over the grains to suck the sugar out) as well as giving you the temperature controlling ability.

 

[MeLoveBeer]

Anytime I check the temp of the mash (so every 30 mins or so), I give it a gentle stir to ensure the temperature is consistent and no colder or hotter areas exist. I generally find that I lose less than a degree during a typical 60 minute mash.

 

[amiddler]

I remember reading a post from Zwickle some time ago and his brewery had a motor that continually stired the mash, I think, for the entire mash time. His comments were that he had an increased efficiancy from this.

Might be best to PM him and ask for info on this first hand.

Drew

 

[Screwtop]

Mash rakes are common place in german breweries, and elsewhere when high Liquor to grist ratios are used. Not common in breweries where lower liquor to grist ratios are used, no need.

Screwy

 

[fraser_john]

Was reading an article in Brewer & Distiller in the Wig&Pen (Canberra) when I was there for two nights for work. One of the large brewery manufacturers is now selling a vibrating mash mash tun, rather than stirring the mash it vibrates it to help the sugar molecules diffuse out through the grain particle. Was a very interesting read.

Be very easy to emulate this with a keg mash tun, just put some rubber feet on the tun and attach high speed motor with an offset weight. Don't think I will be bothering though, my efficiency is about as high as I need to go.

Beers were good too.

 

[Acasta]

Mash rakes are common place in german breweries, and elsewhere when high Liquor to grist ratios are used. Not common in breweries where lower liquor to grist ratios are used, no need.

Screwy

Would it be a good idea then if im doing High Gravity boils?

 

[Zwickel]

In theory, stirring the mash a couple of times during the mashing process should increase the enzymatic activity, i.e. the enzymes are moved around to areas within the mash where sugars are still present that they can work on.

Gday mates,

there are two reasons for permanent stirring: to homogenize the enzymes, as mentioned above and to homogenize the temperature.

A permanent stirring warrants an accurate control over the temp and enzymatic activity.

Here some pics of my setup:





temp probe and water level sensor leads through the lid and the SS ring spreads the sparge water over the mash.


Cheers :icon_cheers:

 

[Thirsty Boy]

Stirring will usually tweak up your efficiency a bit, as will recirculation. But you mare talking about a minor increase, and thats from constant agitation/recirculation. Its doubtful you will get any startling effect from simply stirring a couple of times during the mash.

Stirring is pretty much stock standard in any brewery (commercial that is) that uses step mashing, whether by infusion, direct heat or decoction... They all need stirring. The L:G ratio thing is about cause and effect.. It's not that you don't need to stir a mash with a lower L:G ratio... It's that it's hard to stir (or transfer by pump) a mash with a low L:G ratio, so in breweries that do stir...ma higher L:G ratio is used. A low ratio is used in non-stirred isothermal mash tuns... Because it allows more sparge water to be used, which increases the efficiency of the system and pays back some of what you lose by not stirring.

On the home front... I always stirred my mash when I was batch sparging an isothermal mash... You don't need to worry too much about heat loss. Stir in your mash as you mash in... Get it to temp, let it settle etc... Let it mash for a good 15 or 20 mins. Give it a stir and take a temp... Add some hot water to raise the temp if you like..... But the main thing to remember, is that the vast majority of your conversion has already taken place during the initial 20mins or so.... So after this point, a bit of drift in your temps is much less important and losing a half a degree from stirring won't matter much. But what it will do is give your enzymes a helping hand, reducing product inhibition and increasing substrate concentration... As well as the mechanical action of stirring helping to access extra starches. So all in all... A bit of a stir is generally a good thing for your mashing.

But - and Screwy has talked about this a few times... Stirring can cause a layer of fine gunk to settle on top of your mash... So it can also effect your lautering efficiency. You will need to be aware of that and watch for compacted grain beds and channeling if you continuous sparge.. Shouldn't make much if any difference if you batch sparge though. But you should be giving it a damn fine stir if you batch sparge anyway... So I guess you already know that.

TB

 

[DangerousDave]

jeez mate that is like something from doctor who. it both scares and excites me at the same time :blink:

definitely a beautiful piece of kit though well done :icon_cheers:

Gday mates,

there are two reasons for permanent stirring: to homogenize the enzymes, as mentioned above and to homogenize the temperature.

A permanent stirring warrants an accurate control over the temp and enzymatic activity.

Here some pics of my setup:

View attachment 40379

View attachment 40380

temp probe and water level sensor leads through the lid and the SS ring spreads the sparge water over the mash.


Cheers :icon_cheers:

 

[[email protected]]

+1 for Thirsty boy. Consistant mash stirring is (usually) done on the commercial side and it helps consistant and predictable conversions. This is a major advantage when trying to replicate the same brew over and over. When I brew at home on my system I have a set way I mash as I know what my outcomes will most likely be. I personally stir when I mash and then leave it.

Getting to know your set-up and getting the confidence to trust your process goes a long way to enabling you to brew good beer no matter what style your trying to brew. If something works for you then stick with it. If you can see a benefit in altering your ways then give it a try.

Cheers
Booz

 

[King Brown]

My first AG I just left it and got woeful efficiancy, now I stir roughly every ten minutes and get 75%

Last batch I did was a 90 minute mash, 8kg grist with only 18 litres of water (all I could fit) hit 75% and lost less than 1 degree over the 90 minutes (The main reason I did a 90 minute mash was I was worried I wouldn't hit my target gravity of 1.072 with a mash this thick in 60) After this I would definitely reccomend stirring for high gravity boils. However I know other brewers on here don't stir this much and have no problems.

 

[geoff_tewierik]

Thanks for the info Zwickel.

Any chance you could provide some info on the motor you are using, like power, wattage, amps, rpms?

Been looking at a number of motors of late and wondering whether they'd have enough grunt or turn at enough rpms.

BTW Thirsty, thanks for the spiel, made a lot of sense.

Cheers,

GT

 

[jayse]

[quote name='The Ol' Boozeroony' post='671891' date='Aug 25 2010, 11:19 PM']+1 for Thirsty boy. Consistant mash stirring is (usually) done on the commercial side and it helps consistant and predictable conversions.[/quote]

How common is it in a combo mash/lauter tun though? I wouldn't imagine many would be constantly stirring on top of false bottoms, stirring in the mash tun and only racking in the lauter tun.
I think there would be some downfalls in constant stirring on top of a false bottom, it wouldn't be ideal anyway but proberly depend on what the false bottom actually is and how it is designed.
The stirring I gather would be one of the reasons for having a seperate vessel for step mashing etc.
Not really a issue for home but maybe a question of interest to some.

 

[rotten]

I use a manifold in my mashtun, still relatively new to AG. I stirrred @ 30 min on my last 60 min mash. I did get some, though not much channelling at the rear of my mashtun and a bit at one side. I have put it down to stirring and will try not stirring next time, I may have unsettled the bed? or maybe just lautered too quick? I still hit 75% efficiency and my expected OG, although was worried at the time that I wouldn't hit them. Temp didn't drop. My 2c
Cheers

 

[manticle]

, now I stir roughly every ten minutes

Wow.

just goes to show how different everyone's systems are and how one method cannot be considered the right one without taking into account the specifics of each.

 

[Zwickel]

Thanks for the info Zwickel.

Any chance you could provide some info on the motor you are using, like power, wattage, amps, rpms?

Been looking at a number of motors of late and wondering whether they'd have enough grunt or turn at enough rpms.

BTW Thirsty, thanks for the spiel, made a lot of sense.

Cheers,

GT

Hi GT,

the motor Im using was designed to drive a garage door. Its a 3 phase 400V motor, 120Watts, at around 90rpms

The motor is controlled by a frequency controller (230V in/ 3 phase 400V out) so I can set the rpms from almost still standing up to very high speed.

For mashing the motor is set to around 40-60 rpms, for cleaning Ive set it to around 150 rpms.

Cheers :icon_cheers:

 

[geoff_tewierik]

Thanks for that Zickel.

Will see if I can source a similar type motor here in Brisbane.

Cheers,

GT

Hi GT,

the motor Im using was designed to drive a garage door. Its a 3 phase 400V motor, 120Watts, at around 90rpms

The motor is controlled by a frequency controller (230V in/ 3 phase 400V out) so I can set the rpms from almost still standing up to very high speed.

For mashing the motor is set to around 40-60 rpms, for cleaning Ive set it to around 150 rpms.

Cheers :icon_cheers:

 

[schooey]

Man I love the way Germans build shit... it's just class