Easy espresso brewing for techies

Nowadays many tech companies possess a professional coffee machine in their offices, but how many of us actually worked in a great coffee shop and know the actual basics to pull an espresso? Here I’m resuming the basic steps to set up your machine and to produce a decent single or double espresso shot.

Because cappuccino, americano, flat white, piccolo, and many more coffees start with an espresso shot, you’ll want to get pretty good at this even if you don’t like drinking actual espresso.

Equipment

Having a good espresso machine is important, but try to invest some extra money in getting a good grinder. Remember that even if your home espresso machine makes great coffees it’s not designed for high volume shops and it will very likely break with heavy usage, so if your office has 40+ coffee addicts you will want to invest in a more professional apparatus.

Here at carwow after trying some cheaper models (which eventually broke) we went for a Mazzer, which are simply the best brand and I definitely recommend. They come also in “quiet” version which would be better if your office is open-space.

Coffee beans

Traditionally espresso should be brewed with a blend of Arabica and Robusta beans, though recently we’ve seen a big push for 100% Arabica blends.

Most modern coffee shops use flavour-rich mildly roasted 100% arabica, instead, many Italian BARs still use the classic blend with a darker roast. Personally, I prefer the Italian mix to brew espresso and cappuccino, while the modern style blends are preferred for modern milkier coffees (flat white, mocha, piccolo, etc…).

Espresso theory

Generally, espresso coffees are prepared as single-shot or double-shot. I’m not showing exact numbers but ranges because there are different opinions on how your coffee should taste and it also depends on which type of blend you go for. More traditional espresso making is on the lower end of the spectrum (i.e. 6–8 grams for a single shot), though most street cafes have moved towards the higher end (8–10 grams for single).

Single
Extraction time: 25–33 seconds
Weight: 6–10 grams
Brew volume: 17–28 millilitres

Double
Extraction time: 25–33 seconds
Weight: 12–20 grams
Brew volume: 34–56 millilitres

Start with making doubles as they are easier to brew.

Grinding

Make sure your coffee machine is warm by turning it on at least one hour before use, then transfer the heat throughout the whole system by running one or two “blank” shots. Your cups should also be kept warm, by storing them on top of your coffee machine.

Your grinder is tuned by adjusting the grade of grinding. A finer grind will pour more slowly.

Grind a tiny amount of coffee and pinch a little between your fingers, it should feel quite powdery, keep reducing the grind size until it feels like that.

Take out the basket from the portafilter, put it on your scale and tare it. Fill it with the grinder to get approximately 16g of ground coffee in it.

Extract a double espresso into a cup of which you know the volume, ideally a graded cup. If you don’t know how to pour an espresso, look at the next section.

Ideally, you should get around 45ml of coffee.

It should flow very slowly, a bit maple-like, but not broken in drops, that’s too slow and it means the grinder was set too fine. If the speed is right, time your extraction using the table I prepared earlier and check the quantity extracted, you’ll have to adjust your grinder. Always weight the basket after changing the grinder setup.

Espresso extraction

Take the portafilter with the right amount of coffee ground and tamp it.

Tamping means taking a cylindrical press that fits snugly into the basket and compacting the grounds prior to the shot. The object is to seal the puck so that the brew water moves through it evenly without finding weak spots. Channeling occurs when the pressurised water gushes through the weak spot while not flowing anywhere else, thereby spoiling the shot.

Activate the espresso machine and start pouring, stop the flow as soon as the coffee becomes tan colour with some slight transparency, that colour change means that the right amount of coffee was extracted.

Conclusion

If your coffee extracts perfectly but you think it still doesn’t taste as good as your favourite coffee shop, then you can try to change the type of blend or have your machine checked, it might be the boiler temperature or the water filter.

Hope this helps, in future, we could write about proper frothing and latte art, we have some specialists here in the office.

carwow’s CTO / Co-Founder David Santoro showing off his latte art skills