Mechanical grain stirring

[feralbass]

Hi folks,

I am in the process of building my new cooker, the aim is the BIAB / basket.
The question is; does any one use a mechanical grain stirrer or something similar? Any pics?
I am thinking of locking the basket and setting up small motor and gearbox (say 5 rpm) on top of the pot and stir the grain during the steep and sparge.
Am I pissing in the wind?

Cheers, John

 

[Feldon]

I love the idea of grain stirirng, as an alternative to recirculation of the mash. Bit like liking steam engines over diesels. All that muscular visible movement.

 

[Rocker1986]

I've never looked into anything like that, but I did periodically stir the mash with my mash paddle for a while. I recently stopped bothering with this, and haven't noticed any difference in efficiency or the end product. I wonder if it'd be different if it was constantly agitated?

 

[spog]

I looked into it years back but decided it was too hard,above my skill level. The problem I found was finding a system that was easy for home brewing and was sealed ,as in not letting anything into the mash that wasn't wanted and the other consideration was more cleaning .
In the end I went Biab.

 

[Lyrebird_Cycles]

I'm in the middle of building an automatic stirrer for my mash tun / kettle (the same vessel: I mash out to a lauter tun then return runnings to the mash tun / kettle).

I bought a windscreen wiper motor from Motion Dynamics to use as the drive and will fab up the agitator itself in the next few days (I hope). The motor runs at 65/45 RPM at full noise which will be OK for the boil but probably a bit much for the mash so I'm trialling an intermittent timer. The idea of the timer is to run the agitator for a number of revs then dwell, I'll work the intervals out as I go along (the timer is programmable).

In theory stirring the boil at a light simmer gives similar results to a rolling boil, we'll see.

 

[timmi9191]

The motor runs at 65/45 RPM at full noise

Gear it down, Im sure there a spare sprocket or two in your shed

 

[MHB]

Stirring is only a help/necessity if you are heating the mash (commercially usually steam jacket) making hot water additions, got an element in there...

No point in stirring an isothermal mash, nor a herm/rims type of system, as the hot wort is moving through the grain.
You don't want to be stirring during a sparge (unless its a batch sparge), that would just create a cloudy wort, so you would need to spend a fair amount of time recirculating.
Think it through before you go to the trouble of fitting a stirrer, I suspect a pump and a herms/rims is a better option.
Mark

 

[Lyrebird_Cycles]

It wasn't clear in my post that the lauter tun is a separate vessel, I've amended it to make that clearer.

I use multiple temperature mash profiles and heat via induction.

 

[feralbass]

Thanks for the replies guys.
Mark, i am fitting a pump and was going to run the pump as well as the stirrer at the same time, (I should have mention that).
So what you are saying is, not to stir the mash during the sparge, i can see the logic in that.
Would you recommend a spray bar to be used during the sparge?
I have never done or seen BIAB batch, so I am trying to build around ideas and information picked up along the way.
My plan is to do the seep, lift the grain, drain the grain, empty the work from the cooker into a cube, heat a new batch of water, replace the grain and run the pump thru the grain to sparge, lift and drain the grain, remove, return the wort and do the boil.
Does this sound feasible?
John

 

[MHB]

Sounds to me like you are doing a lot of extra handling to little gain.
Given that your kettle is big enough to boil your whole wort, it would be nearly big enough to do an all in classic BIAB.

Couple of things that might complicate your process-
The wort in the cube (first runnings) will still be mashing, there are live enzymes in there and they will continue to modify the wort, might lead to unexpected results.
The idea of recirculation is to 1/ build up a filter to clarify the wort. 2/ increase the temperature of the mash to optimise for different enzymes and to mash out - ending enzyme activity when the right mash profile is achieved. 3/ keep the whole system homogeneous, same temp and SG through out.

Pumped recirculating systems are best if the wort travels through the grain, top to bottom or bottom to top. Problem with a bag or basket is that the wort can run out the sides so some of the grain is heated/rinsed les than other parts, worth investing in a basket with solid sides.

If you haven't done any BIAB brewing I would start out super simple, buy a bag do a couple of simple all in no sparge beers and when you have your head around what is happening, add any extra refinements to your system over time.
Don't get too worried about batch size and efficiency, work out how much you can do comfortably and safely - get the basics right.

Go to the "All Grain Brewing" tab and have a read of the basic BIAB guides.
Going to say this again - Get the basics right!

Post the size of your kettle and the type of beer you want to make, if you want a few more ideas on how to progress.
Might be worth ordering a couple of recipes from a good retailer, so you can do the same beer back to back.
Mark

 

[Ducatiboy stu]

I always found stirring the mash to be helpfull in getting a few more % points, and I use batch sparging

I dont stir during sparging, but I do when mashing and in between sparge runs

 

[feralbass]

Mark, your point about the basket having solid sides is something I have been thinking about, this will allow me to make the basket locked in place for the mechanical stirrer, not hard to knock 1 up, I didn't like the mesh 1 i made anyway.

I've been brewing kits and bits for years and now days use a fair bit of grain with my kits,and producing some really nice brews, this is what is making me head to BIAB. I've been using a 9lt pot on a propane camping stove.

When I get this cooker complete, i was hoping someone in Syd would be willing to show me the ropes, I make a good apprentice. You can read lots of articles but nothing is like being shown live, color and smell changes etc.

You are correct in getting the basic right, I have make enough dumb mistakes over the years to get this far.

The electric element turned up today for the cooker but the laser parts for the jacket were not ready, bummer.