Taming light roasts with the Digital Pre-infusion Module #1

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One of the features I was keen to enjoy is the option to 'tame' the modern light roasts, extracting them at higher pre-infusion pressure which enables the group to fill more, and start the extraction with a more compressed spring on the lever as the lever 'catches' at horizontal or even a little below that.

I went out and bought a few bags of beans from a roastery that's well known for their very light roasts and tried a first bag, getting a lovely full bodied shot, spicy, with none of the nasty acidity that a low-pressure pre infusion would yield.

Before, I would only drink that coffee at the cafe where I got the beans as they have adjusted their machine to compensate well for the light roast.

Now I can easily adjust my own system to accommodate that light roast. I will next (today or tomorrow) try the even lighter ones roasted for filter.

I had expected to have to grind (much) finer but as it happens, the high pre-infusion pressure and the much higher initial extraction spring pressure compresses the puck more which also proportionally helps to restrict flow.

Got 3 light roasts

Tried this one first at Tonino #107

Set pre-infusion pressure to 6 bar (static pressure measured 7.5 bar at that moment)

Lever 'catches' a little below horizontal




No one would guess this was a 'light' roast ;-)

Reacties

Bas zei…
Very intersting mod. Best of two worlds. With this mod you get the advantage of both a traditional lever and modern pressure profile machine. Very flexible system in this way!
12 december 2018 om 03:50
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