I’ve lost count of how many times someone asked me to create both single and double espresso out of the same coffee with the same grind setting, that also both taste the same! It’s a physical impossibility, as a single espresso requires a much finer grind size to achieve similar levels of resistance to the pump. Fortunately there are some neat strategies we can employ with Eversys machines to bring them closer to each other. They may not be the same, but our compromise will be reduced to the absolute minimum.

Firstly, I calibrate the double espresso. This will be the recipe that the machine uses for “ETC” calibration: choosing its grind size and time to follow this recipe. We can’t have more than one ETC recipe because the machine will never be able to make the right decisions. It’s important for the double espresso to be our ETC target as the using the single espresso for ETC may see our double espresso’s shot time blowing out to 35+ seconds. For the double’s recipe there are some particulars to follow closely:

- no preinfusion

- -3 mm 2nd tamping, for extra head room

- 20kg tamping pressure

- 27-32 second ETC target extraction time

With these three variables set, the machine will be forced to use a finer grind than usual to make the double espresso. This means that our grind setting will be closer to optimum for the single espresso! Now for the single espresso we do the complete opposite, using every variable to our advantage that can slow down the shot.

- preinfusion and long relax time

- +5mm 2nd tamping, to keep the coffee compressed during brewing

- 60kg tamping pressure

With this combination of variables for both recipes, we have a double espresso extracting in around 27-32 seconds, and a single espresso that sits just below. The single espresso’s extraction time isn’t being optimised and adjusted for, but we know it won’t be too much faster than the double, and it’ll definitely never be slower. A fair compromise for a tricky problem!

To the boundaries of coffee,

Matt Perger

Barista Hustle