Espresso is one of the most elusive and ethereal of all coffee drinks. It sometimes seems as if there are as many opinions on espresso as there are people who drink it. There are however some basics to espresso that can help bring it down to some basic components of flavor and preparation that will point you in the direction of further personal exploration and discovery.
Espresso is made by forcing hot water through finely ground coffee at a specific pressure forming an emulsification. The resulting drink is thicker than regularly brewed coffee with finely concentrated flavors and a thick crema on top. Espresso is not a specific type of coffee bean or roast, but a specific brewing method. There are many, many ways to roast coffee for espresso brewing from complex blends of 4-5 different beans, each lending its own quality to the mix, to fine single origins which lend themselves to this particular brewing method. There are coffees that taste great on their own, and others that blend extremely well with milk to make lattes, cappuccinos and other espresso based drinks.
So other than the coffee, there are some practical components to brewing espresso that will yield the best cup. Slight variances can dramatically affect the taste of a shot of espresso and again, experimentation will lead you to the extraction that best suits your own personal tastes.
First is the grind. This will affect how fast, or slow, the water will push through the coffee. The coffee should feel a bit like fine beach sand when you rub it between your fingers.
Second is the dose. A single shot is between 7-9 grams of coffee and a double is 14 – 18 grams.
Third is the tamp. Hand in hand with the grind, this will also affect the water will flow through the coffee. 30 lb. of pressure is the standard measure. You can test this on a home scale to see how hard you’re pressing. Alternatively, there are several mechanical tampers with a built-in 30 lb. click stop so you’ll know exactly how hard you’re pressing.
Fourth is the brewing time. You should produce about 1 oz. of liquid in 25-30 seconds. A double shot will produce 2 oz. of liquid in about the same time.
A few other variables that will help you along the way. Make sure your portafilter is hot and your machine is fully warmed up before making an espresso. A warm cup will also help to maintain the integrity of the brew as temperature stability is a big function of a great espresso. Humidity and age of your beans will affect the outcome. You may find yourself adjusting the grind as the ambient temperature changes and your beans age. On that note, try to buy only as much espresso as you’ll use in a 7 day period.
The last thing is to have fun during your journey. Stay tuned as well begin hosting espresso brewing classes this fall.