One basic tenet of coffee or espresso brewing is that the grind makes the coffee. It is not difficult to understand that if you put a fine espresso grind into a french press the coffee will come out sludgy and over-extracted. Likewise, if you try to use a coarse press grind for espresso the water will rush through, barely extracting the coffee’s delicious flavors. Until recently I did not understand the subtleties in grind, however.
A few weeks ago I became the proud owner of a Rancilio Silvia with a PID (temperature control). I immediately set up the machine and went to pull my first triple with the Rancilio’s flat-bottomed portafilter (unlike traditional portafilters, this one has no “ears” on the bottom, and instead is perforated. As the espresso pulls through the portafilter it coalesces into a single stream in the middle… at least in theory). I turned on the machine, let it warm up, ground my coffee to my usual espresso grind, and pressed the pull button… espresso spurted everywhere.
I tried a finer grind, I tried a coarser grind, I tried a traditional portafilter, I tamped with all my might, but still every time I tried to pull a shot my kitchen ended up covered in espresso. Even on the finest grind my burr grinder could manage, this high-pressured machine blasted water through the portafilter like I had forgotten to pack the espresso.
I needed to change my tactic. I still was not positive about the nature of the problem, but thought maybe it was not my machine after all, maybe it was… my grinder. So I went down to Oren’s Daily Roast and talked with one of the baristas there. He sold me coffee in 3 separate grounds: #5 (their traditional “electric espresso machine grind”), #4 (slightly finer), and #3 (the grind Oren’s uses for its industrial machines).
The #5 was useless, with water still spurting through, but the #4 was slightly better, which gave me some hope.
Then I packed the #3. I poured in 3T of coffee and tamped with all the strength I had. When I first turned the machine on I wondered if I had run out of water, nothing was coming through the portafilter. Then ever so slowly espresso started to drip through and form a slow, thin stream from the middle of the portafilter into my shot glass. 40 seconds later I had the thickest triple espresso I have ever seen sitting before me.
Now, 40 seconds is not at all ideal (~20 seconds is supposed to be the target), but I was very happy to know I could do it! It is all in the importance of the grind, both finding the right grind for your bean and for your machine.
Now to find a new grinder…