Stirring vs recirculating

[kanzimonson]

Most people have noticed that they get a few extra efficiency points when they stir the mash a couple times during saccharification. Do you think you'd get the same benefit by using a pump to recirc for a bit?

It seems to me that the benefit of stirring comes from the fact that you're almost forcing the starches and sugars out of the thicker pieces of grain and moving stuff around.

When it comes to recirculating, on the one hand you'd be moving things around in the mash, and hopefully you'd get some fluid motion for the starches, but I suspect it wouldn't be as through as an actual paddle/spoon smashing stuff around.

Thoughts?

 

[Yooper]

Yes, I definitely get a higher efficiency when I run my HERMS.

Some breweries have a "mash rake" to stir the mash continuously to squeeze out every bit of efficiency they can from the grains.

 

[remilard]

Stirring is high shear which may be better for efficiency but also may cause some problems (commercial mashtuns with rakes are designed to be low shear). I'm not sure with the amount of stirring a homebrewer would do manually it really matters for good or bad.

I get about the same efficiency batch sparging with a RIMS as I did in a cooler with some stirring. I get higher efficiency fly sparging with the RIMS.

At the end of the day I would neither choose nor reject recirculation because of this particular issue.

 

[kanzimonson]

Thanks for the replies. I was hoping this would be the situation. I certainly like recirculating over stirring just because you're not disturbing the grain bed.