A quick introduction to my classroom environment.
This is the classroom. It’s got a chemistry lab feel about it doesn’t it? Guess what? That’s exactly what it is.
This is my Texas Instruments scientific calculator. We call it a Nuova Simonelli Aurelia.
This is my protractor (a.k.a. Mazzer Robur grinder).
Ruler (kitchen scale with 0.1 gram resolution)
And pencil (tamper).
And this is Mr. Hockin (I call him Professor Hawking when he’s not paying attention). He’s a mysterious espresso scientist. Some say he’s some kind of coffee vigilante or ninja or something by night. Look at that photo. All I know is it makes me nervous that he can move a portafilter that fast.
My first tamp
We covered the very basics today: grind, dose, distribute and tamp.
Grind
To pull a quality shot you need to grind your coffee right before you brew. Subtle changes courser or finer can have a huge impact on the way the shot pulls (to be covered in a future lesson).
Dose
Dosing basically means using the right amount of coffee. At Transcend we typically use around 20 grams in a double portafilter basket. With the Mazzer Robur grinder you need to be careful to first purge any old stale coffee that’s in the chute between the burrs and the dosing chamber. The Robur is a manual dose grinder that means you need to grind then pull a lever to deliver ground coffee into the portafilter. Technique is important. I’m told to pull three times, then tap the portafilter (to settle the grounds) twice, then pull twice more, tap three times, then pull as many times as it takes to fill the basket. I think it will be on the test.
Distribute
It’s important to distribute the coffee evenly around the portafilter. There are some tricks to this. Prof. Hawk showed me how to move my right index finger from the left side of the portafilter down to the ‘six o’clock’ position. Then use my index and middle finger in a V (the european foreign exchange kids will loove this one) to move from six o’clock to twelve o’clock, then back down to six and up to twelve making ’24 hours’ of coffee distribution. Then pat any remaining mound of coffee gently down using a horizontal index finger down and back up again ‘sun set and sun rise’. I know, teachers can be such dorks, but I actually think this will help me remember.
Tamp
Tamping compacts the coffee so that the hot pressurized water will have a more difficult time moving through the grounds and will extract more oils and espresso-ey goodness. The technique is to rest the portafilter on the little rubber mat thing (or counter) hold the tamper like you’re shaking its hand (it’s a friendly tamper) keep your forearm as vertical as possible, with close to a 90? elbow and press evenly with about 30 lbs of pressure. Release the pressure, and give the tamper a 90? spin. Remove the tamper, gently place the tamper above the lip of the portafilter at twelve o’clock and push down very gently just to move any grounds that may have stuck on the sides of the portafilter wall down to the level of the coffee. Repeat at three, six and nine o'clock. Then go back for one more full tamp at 30 lbs of pressure, release pressure and gently spin. The result should be a nice level, smooth surface of coffee. My first attempt was not very level at all. In fact it took me several attempts to get a tamp that satisfied both Prof. Hawk and me.
We tasted a number of shots that were deliberately wrong. We tried under-dosed (too little coffee) which results in over extracted, bitter espresso, over dosed which turned the shot sour, and unevenly distributed, which pours poorly and is just generally unpredictable. It’s a good idea to spit when tasting and training on espresso—not only so you won’t be up all night nervously rearranging your transformers collection by size, colour and appearance in the original animated movie (not that Michael Bay abomination)—but because the vast majority of shots, especially when experimenting, will taste just... nasty.
