Different Coffees, Different Shot Volumes on La Pavoni

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mrbananas
Posts: 32
Joined: January 5th, 2016

Postby mrbananas » May 07, 2016, 4:56 pm

Hi folks,

I'd like to understand something I observe happening when pulling shots on my Gen 3 La Pavoni with different coffees dialed in to different grinds. When I lift the lever a single time to pre-infuse, then pull the shot after about 8 seconds, I find that the amount of liquid I get in the shot varies quite a bit from coffee to coffee.

For each shot, I grind 15g of beans. The results I get for different beans are as follows:

Sulawesi, roasted City+, pretty hard/dense bean, roasted a bit finer: 25-27g
Natural processed Guji Hambela roasted City+, more delicate/softer bean, roasted a little coarser: 17-20g.

These grinds are what I've dialed in for best flavor after experimentation. To satisfy my taste in espresso, I compensate with an appropriate amount of Fellini pumps to reach around 37-40g, and my result then is pretty enjoyable.

Mostly out of curiosity, I wanted to get some insight into what's causing the differing amounts of espresso output. Intuitively, I would've expected the coarser grind / softer bean to create more of a pressure disparity between the group / boiler and thus result more water flowing from the boiler. But that's clearly not what's really happening :-)

Thanks, Eddy

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drgary
Team HB
Posts: 9828
Joined: February 7th, 2010

Postby drgary » May 07, 2016, 5:25 pm

Gary
LMWDP#308

What I WOULD do for a good cup of coffee!

 
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