Preinfusion

[Niko]

Here's a clip showing preinfusion set for 6 seconds @ 40psi.

http://www.youtube.com/watch?v=tTWTntowF8I

The coffee is a single farm (to be named later :D ) after I create the perfect roast profile on the Hottop.
The shot in this particular clip almost floored me and I almost didn't live to tell about it...
it was THAT GOOD.
This bean was roasted until the first audible second crack and then stopped immediately.

[PBL]

Nice video, seems to be very effective. The esprosso shot looks marvelous. Thanks Nilo. :D

[coffeeowl]

mmm this silence after the click sounds intriguing... :) :D

[JohnB]

mmm this silence after the click sounds intriguing... :) :D

Especially when no water comes out for several seconds!. I've noticed that the p/i needs to be primed by the first flush of the day. After the 1st one the water comes out immediately after the click but there is a delay of several seconds the first time. Even after a 2-3 hour idle period there will be a 2-3 second delay before you get any water on the 1st flush.

[chas]

Since everyone should be doing one or two warming flushes anyway, this shouldn't add any extra steps.

[boldstep]

Great video Niko! Thanks for posting it.
A few questions as I start reading through all these p/i threads and jumping on the p/i bandwagon :
(1) Do you count the 6 seconds in your total extraction time? I did notice you started the timer *after* p/i finished...
(2) When you use 40 psi, I would assume that your group head pressure is also a effected, right? Or are you adjusting those independently somehow?
(3) Have you played around with different line pressures and found 40psi to be the tastiest?

[Dan Bollinger]

I've noticed that water doesn't begin to flow immediately if the machine has been idle for a while, probably because the water has evaporated. I'm not in the habit of hitting the double-dose button while I'm grinding the first cup of the say so that when I pull that first shot the puck gets preinfused without delay.