Last week I started writing about my long and winding espresso extraction journey...
Let's move through a few of the stepping stones today.
- Grinder burr set - conical to flat;
- Pre-infusion;
- Portafilter baskets - Sworksdesign.
Last week we talked about grinding finer with VST baskets. Today I'll quickly talk about burr sets, pre-infusion and the Sworksdesign stepdown billet basket. I'll leave dynamic shower screen springs and the CremaLoop slow feeder until later and each of these deserve their own dedicated blog post.
Moving from conical burrs (Lyn Weber HG-1 grinder) to large flat burrs (KafaTek Monolith Flat) increased the clarity of the espresso but also slightly reduced the viscous texture of the output.
Adding pre-infusion to the mix was a big change. I had our coffee machine customised in Melbourne with a second water circuit controlled by a needle valve allowing me to pre-infuse at 2 bar of water pressure prior to applying the full 9 bar for espresso extraction. My typical routine is to pre-infuse for 20 seconds, just about the time when I see the first drops of the espresso extraction, and then ramp up to full pressure. Pre-infusion meant that I had to grind a lot finer which increased flavour intensity and also increased viscosity and texture.
And then I started using the Sworksdesign stepdown billet basket. There was a decrease in ground coffee dosing from 25 g in the VST to 20 g in the Sworksdesign but no change in grind setting. The aspect ratio change for the narrower basket now means that the espresso shots taste more balanced and elegant.
I've deliberately saved the best and most interesting findings to last. In the next couple of weeks well dive into some detail around dynamic shower screen springs and slow feeding. See you then!
To read about latte art click here
To learn about coffee bags click here
To hear about coffee produced by Guatemalan women click here