What is Espresso?
Espresso began as an attempt in the 1800s to quickly brewThrough the decades, the elements of espresso brewing
coffee on demand, by the cup. The goal was to serve thewere tested and refined to produce the standards we have
freshest, most flavorful coffee possible and avoid thetoday: one cup (30 ml) of true espresso comes from
burned, stale taste of coffee kept warm on a stovetop. Toexposing 7 grams of finely ground and packed coffee to
speed the brewing process, coffee pioneers struck upon the90�961 C water under 9 bars of pressure. In a brief 25
idea of forcing water through the grounds under pressure.seconds, most of the highly flavorful coffee aromas and oils
Steam was initially used to supply the pressure, followed byare extracted, while the more bitter compounds and off-
compressed air, lever operated pistons, and finally, thetastes are left behind.
electric water pump. When the ground coffee is fresh and the brewing is done
Englishwell, the pressurized brew water emulsifies the coffee oils
into the golden foam called crema, which crowns the
espresso with ultimate flavor and aroma.
Overextraction and Underextraction
Brewing great espresso takes an understanding of whatIf ground coffee steeps in water too long, all the soluble
actually winds up in the cup when coffee is exposed tocompounds will be extracted, which makes for a very bitter
water. Roughly 30% of a roasted coffee bean is made ofbrew. This is called overextraction. The opposite of
water soluble compounds. 20% of those compoundsoverextraction is underextraction, which occurs when coffee
dissolve fairly easily, while the remaining 10% take a littleis not exposed to the brew water long enough, leaving the
more work � which is a good thing, because that less-essential flavors and aromas locked in the grounds.
soluble 10% is acidic, bitter, and generally unpleasant. TheUnderextraction results in coffee that is weak in taste.
goal of all coffee making is to extract the easily dissolvedWhether brewed coffee is overextracted, underextracted,
oils and compounds while leaving the rest in the grounds. or just right depends on several factors, including the ratio
of coffee to brew water, the fineness of the grind, the
brewing temperature, and the length of time the water is
in contact with the coffee. All these factors are either
directly or indirectly affected by the baristaOs technique.
Before Brewing: The Elements of a Great Espresso
Before the espresso machine is even plugged in, youOll needGreat Tasting Water
several elements to produce great coffee.
An often overlooked element of great espresso is the brew
Fresh Coffee Beanswater. If you donOt enjoy the flavor of your tap water, donOt
Great coffee can only come from fresh coffee beans,use it to brew espresso � use bottled, purified water
properly roasted. Many baristas recommend buyinginstead. Since it doesnOt take long for fresh water to
acquire a Oflat� quality and taste, itOs also a good idea to
beans roasted no darker than a medium roast, the colorchange the water in the tank often and refill the boilers
of which appears as an even chocolate brown. This roastafter a long period of non-use.
preserves the natural sugars and flavor of the bean,Do not use mineral water or distilled water � they can
which sets the stage for excellent espresso. A mediumdamage the espresso machine.
roast is the darkest a bean can be roasted without oils
developing on the surface. The Right Grind � and Grinder
Darkly roasted beans � which appear dark brown or
nearly black � look great, but the extra roastingEspresso demands a very fine, very consistent grind. Blade
overwhelms the more delicate coffee flavors andgrinders and inexpensive burr grinders usually fall short
caramelizes any sugars. A heavy Oroasted� coffee flavor,when it comes to producing the grinds needed for
often bitter and sharp, will predominate with a dark roast.outstanding espresso.
The best espresso requires a quality burr grinder, like the
To preserve the freshness of Artisana Burr Grinder. A good burr grinder will maximize
coffee beans:the flavor and aroma of espresso by producing an
extremely consistent grind with very little frictional heating.
Keep beans in an opaque, air-tight container and store
them in a cool, dry place. Refrigeration is not
recommended, as condensation tends to form on the
beans whenever the container is opened. Freezing can help
preserve beans stored for an extended period, but it will
also impair flavor.
12 |
ACEC
