Hello, Gang!
So let's have a talk about the venerable La Marzocco Linea EE (that's the one with the auto buttons, I believe) and everybody's third-favorite dicussion topic: Pre-Infusion!
There is (has been?) some talk about using different sized gigleurs (
link) to reduce the flow rate to the grouphead in order to physically force the LM grouphead into a sort of soft infusion and slower ramp-up to full pressure.
(http://coffeegeek.com/forums/espresso/machinemods/439567)
There is also some chat (
http://coffeegeek.com/forums/espresso/machines/419375) about the use of gigleurs vs. the use of paddle-based grouphead design.
But, is it not the case that with Linea EEs, you can program in a pre-infusion? The question is mostly rhetorical, as I know that you can, and I have, and it works, at least insofar as it engages the pump momentarily, pauses, and then applies the remaining pre-programmed shot volume. However, the swirly-infinite button and semi-auto toggle DO NOT then utilize the programmed pre-infusion.
So, how do we mod our grouphead, gang? Do we install gigleurs so that our more experienced baristi using the semi-auto toggle get the same pre-infusion (or at least SOME kind of pre-infusion) as our rookie baristi who are still using the volumetric controls? It would seem that a Linea EE programmed to pre-infuse and fitted with a gigleur is going to manifest its pre-infusion in a pretty soft way, and might be worth trying out.
I am not convinced that pre-infusion is the way to go at our shops, but it seems that there are a number of options here (not including paddle installation)
1.) Leave the machine as is, programmed without pre-infusion
2.) Program machine to use pre-infusion on the volumetric buttons
3.) Install gigleur to reduce flow rate and create a slower pressure ramp
4.) Program for pre-infusion AND add gigleurs
Any thoughts?