I've remained a barista at heart, even as my knowledge and duties have expanded to coffee tasting, green coffee analysis, and teaching at illy's Università del Caffè. One of my biggest honors was winning the title of Italian Barista Champion a few years ago. For baristas, training is everything, and teaching my craft is my favorite thing to do. Too often, those who drink or prepare coffee, even so-called "experts," don't pay attention to what they are doing, which is why illy asked me to spend all of 2010 in the U.S., to educate both coffee lovers and professionals.

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The American reality, a need for more training, was not a surprise for me. But what I didn't expect were so many baristas using so many methods to prepare espresso, far from the authentic Italian technique. Once you stray from the formula that international associations agree on, espresso is no longer espresso.

The biggest mistake I've seen is an enormous quantity of coffee being used—way too much. I'm talking about 20 to 25 grams of coffee for a single espresso shot! It is like making a mojito with half a mint leaf, one ice cube, a few grains of sugar, and a gallon of rum. Undrinkable!

Espresso made this way—well, it's not espresso, but I'll call it that—turns out overly concentrated, and because of that it cannot delight the drinker with the magnificent aromas of toasted bread, chocolate, red fruit, orange, and jasmine flowers that are all present in a high-quality blend.

The beverages I tasted were almost syrups, full-bodied but with a very sour, almost salty taste. I suspect that beans that were roasted too recently played a part. After roasting, beans need a few days to breathe and mature. These too-young beans are a big problem. Also, I've visited too many coffee bars that don't heat cups before serving, and in the process sacrifice flavor and aroma. Or that serve in wet cups, an espresso sin.

An espresso, a real one, requires seven to eight grams of freshly ground coffee roasted two to three days in advance, or preserved using pressurization. The water can't be too soft, and must not exceed 200 degrees F to avoid burning, nor be lower than 190 F in order to extract all the best aromatic components.

The grind is also fundamental. A too-fine grind can create burnt coffee and extract unpleasantly bitter and woody flavors. This is why so many people describe espresso's taste as "bitter." An overly coarse grind doesn't permit full extraction of certain key elements. The proper, medium grind permits extraction of one ounce of aromatic black liquid in 25 to 30 seconds, the ideal amount of time.

If all these variables are respected (amount of coffee, temperature, time, and volume), along with the right pressure (around nine atmospheric units or 130 psi), you get an opaque, perfumed liquid containing microscopic oil droplets releasing precious coffee aroma, set fully free on your taste buds.

illy

A silky, persistent foam ("crema") will appear on top, nut brown with red stripes, protecting the liquid underneath for a few minutes—just enough time to hold that ceramic cup in hand, feel the warmth, move it to the lips, and sense those freed aromas in the mouth, where they will combine to create a unique taste experience.

Otherwise known as espresso. A real espresso.

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