I’ve devoted irresponsible hours and dollars to the pursuit of creating perfect espresso coffees at home. Here are some of the important things I’ve learned – via many bad cups of coffee – along the way.
Espresso is the art – and it really is an art – of extracting crema from coffee beans. A very delicate balance of bean grind, temperature, tamping and water pressure is required to extract optimal crema. You need good equipment, good beans and good technique… there are no shortcuts.
- Buy your beans from a serious coffee shop. Supermarket and chain store beans are usually old and stale.
- Very cold, full cream milk is necessary to create the right “mouth feel” of cafe quality lattes and cappucinos.
Invest in good equipment. Even the best baristas cannot make good espresso with bad equipment.
The most important piece of equipment is the grinder. You need a burr grinder, which will shave the beans into powder, and not a herb grinder, which will tend to crush them.
You’ll need a good espresso machine, too. Unfortunately, most mass marketed home espresso machines aren’t up to the task. They deliver insufficient sustained heat and pressure, and use technological sleights of hand (eg “crema disks”) to create the appearance of a good coffee, without the actual taste of good coffee. Push button models which seek to automate the crema extraction process are the worst, because they don’t take account of the condition of your beans, variable grinds, and other significant factors which vary from cup to cup.
I currently use a Rocket R58 V2 espresso machine, having moved on from a Rancilio Silvia and a Breville Dual Boiler. I have paired it with a Rancilio Rocky burr grinder.
After a while you can judge the optimal temperature of frothed milk by touch alone. But until then, a milk jug thermometer will help you heat milk to the correct temperature. They’re available at any kitchenware store, and many coffee franchises.
Technique – Espresso
This is not intended to be a complete guide to the process of extracting espresso. Rather, it lists the most important things I’ve learned from experience.
- Pre-heat your espresso machine’s head as well as your cup. You need the temperature of the water to be consistent from machine, through head, to cup. I run water through briefly before each extraction.
- Adjust the fineness of the bean grind for each cup. Too fine will burn your coffee and clog your machine. Too coarse and you will not extract sufficient crema. Don’t be afraid to waste a couple of draws to get the grind right.
- Grind your beans just seconds before you use them. Ground beans lose a lot their flavour within minutes of being exposed to the air. Even the airspace in an airtight container will suck considerable flavour from pre-ground beans.
- Tamp your coffee down moderately hard into the espresso group head. 25 kgs of pressure is often about right… though this depends on the grind and freshness of the beans.
Technique – Milk*
Cafe quality lattes and cappuccinos require smooth, creamy milk microfoam.
- Purge some steam through the steaming wand before inserting it in the icy cold full cream milk.
- Insert the steaming wand on roughly a 45 degree angle to the inside of the milk jug, sitting it just below the surface of the milk so it draws in air as well as steam.
- Hold the milk jug still, and use the angle of the steam hitting the wall of the jug to create a whirlpool effect in the milk.
- Continue to gradually draw air into the milk, by lowering the jug as the froth grows, until it reaches about 40 degrees.
- At 40 degrees, drop the tip of the wand under the surface.
- At 67 degrees (no hotter, or you’ll burn the milk) remove the wand and give it a quick clean with a damp cloth.
- Tap the bottom of jug on the counter to “flatten out” any air bubbles on surface of milk, and make it more dense.
* Note: The section on Milk Frothing Technique was kindly contributed by fellow coffee connoisseur, Edwin Betts.