Pressure vs time

CoffeeLover01

Hi, I am trying to improve my technique pulling shots.

I wonder why the brew pressure and shot time vary from one seemingly similar machine to another (using the same beans, same grinder and same tamp pressure)?  Is there an optimal brew pressure and time (by adjusting the fineness and tamp pressure) to pull a 2oz shot?

Thank you.  ;D

Koffee_Kosmo

on 1479208612:

Hi, I am trying to improve my technique pulling shots. I wonder why the brew pressure and shot time vary from one seemingly similar machine to another (using the same beans, same grinder and same tamp pressure)?  Is there an optimal brew pressure and time (by adjusting the fineness and tamp pressure) to pull a 2oz shot? Thank you.  ;D

The same can be said about different makes of cars Why do different makes drive differently yet they all go from A to B As the driver / user of machinery you adjust your technique to suit the machine KK

LeroyC

on 1479208612:

Hi, I am trying to improve my technique pulling shots. I wonder why the brew pressure and shot time vary from one seemingly similar machine to another (using the same beans, same grinder and same tamp pressure)?  Is there an optimal brew pressure and time (by adjusting the fineness and tamp pressure) to pull a 2oz shot? Thank you.  ;D

Yes there is an optimal brew pressure and extraction time. There's also an optimal dose, yield and temperature. All these variables are relative though and are specific to the situation, i.e. the coffee being used, the machine being used and the desired result. Base everything on the result in the cup. There's no point deciding on a set of parameters before you pull a shot then sticking to them regardless of how the espresso tastes. Set things in this order - dose, yield, time/extraction. Don't use differing tamp pressures to make adjustments. Tamp pressure shouldn't really matter, what's important is good technique and consistency. It should be a variable that's the same every time. So if I have an 18g basket I'll pick a dose, let's just say 18g to make it easy. Then I'll decide on a brew ratio, let's use 2:1 for this example. That means my yield will be 36g. And I reckon a 31 second shot will give me a good result for this coffee on this machine. The 18g can be controlled each time by weighing the dose, and I'll shoot for a 36g shot in about 31secs. I'll watch the extraction and taste the result. I'll adjust the grind if needed to achieve the best result in the cup. I'll only adjust the other variables of time, yield and dose if necessary, working backwards through them and adjusting one at a time. As I'm just making coffee at home I generally only go through this rigmarole once when I change to a new coffee. After that it's all by feel, based on previous experience. It's rare that I'll sink a shot, but I will if I have to.

Brett H

Great post Leroy! I started to write something but really seriously couldn't keep it under 25,000 unintelligible words.

K_Bean_Coffee

Yes, great post Leroy