Pump for dry hopping

[Allard]

We dry hop our beer by adding pellets directly to the beer and then recirculate the beer for 24 hours, using a centrifugal pump. The pump is not adjustable in speed and it pumps at about 11 m3 / hour. So... kinda fast.

I am worried that using a centrifugal pump like this will create too much shear force and break apart coagulates, thereby impairing clarification of the beer. Also, I wonder if this method of dry hopping will result in an increase in astringent flavors.

What are your experiences or thoughts on what kind of pump to use for dry hopping this way?

Thanks,
Allard

[UnFermentable]

You say that you are doing this method, but also say that you are worried about it....have you seen evidence to justify your concern? Astringency? Turbidity?

Yes both those CAN be problems associated with recirculating hops. A centrifugal pump is not ideal, but can be used - a VFD would be HIGHLY recommended. Slow is your friend.

There is a lot involved with polyphenols and hazes, as well as circulation and extraction. It is basically trial and error, but in general more circulation equals faster/more extraction. Temp plays a role. The more you circulate, the sooner you should dump.

[Derrick]

We dry hop our beer by adding pellets directly to the beer and then recirculate the beer for 24 hours, using a centrifugal pump. The pump is not adjustable in speed and it pumps at about 11 m3 / hour. So... kinda fast.

I am worried that using a centrifugal pump like this will create too much shear force and break apart coagulates, thereby impairing clarification of the beer. Also, I wonder if this method of dry hopping will result in an increase in astringent flavors.

What are your experiences or thoughts on what kind of pump to use for dry hopping this way?

Thanks,
Allard

With centrifugal pump for dry hopping is OK, of course by VFD control to adjust pump speed is more helpful. But if you still worry about the shear force, a diaphragm pump is a better choice, which is more gentle.