Decoding Espresso: The Unforgiving Art of Coffee Extraction

In the world of coffee, few beverages command as much attention and scrutiny as espresso. Whether enjoyed straight, or as the canvas for other ingredients, it has captivated coffee lovers for generations. But what exactly is espresso? How did it come to be the centerpiece of coffee culture in so many parts of the world? Can we provide a global definition for a drink that has been woven into the fabric of so many cultures with varying opinions and techniques? In this article, we delve into the origins, evolution, and definitions of espresso, aiming to unravel the intricacies of this beloved brew.

To understand the essence of espresso, we must first explore its origins and development from technical, historical, and societal perspectives. Similar to the steam trains that fueled Europe's industrial revolution, espresso owes its creation to Angelo Moriondo's 1884 patent, which set off a chain reaction in Italy. Prior to that, steam-powered machines for faster filter coffee brewing existed on a smaller scale in France and England. However, Morando's invention revolutionized the process by increasing brewing pressure to 9 bars, allowing for a finer grind which resulted in a faster brewing time, and the development of crema—a defining characteristic of espresso. This technological leap laid the groundwork for the spread of espresso across Italy and eventually to other parts of the world through emigration.

The evolution of espresso has been closely tied to advancements in coffee machine technology. The shift from lever machines to electrical pumps brought about a more consistent pressure profile, and ease of operation. Separating coffee brewing water from the steam boiler allowed for a higher-quality espresso brewed at a lower temperature and continuous steam supply for milk foaming. These developments paved the way for dedicated water in a better temperature range for brewing espresso. Subsequently leading to further exploration of coffee’s potential and a continuous cycle of innovation from seed to cup. Today, espresso machines have become central to beverage production in both professional and home settings, offering a wide range of espresso and milk-based drinks from a single machine.

Defining espresso is no easy task, as various definitions and parameters exist. The name "espresso" originates from the Italian word for "express," reflecting both its fast preparation and the pressure involved in its brewing process. The National Institute for Italian Espresso provides precise technical parameters for espresso preparation, including specific coffee blends, water temperature, pressure, and extraction time. However, these strict parameters may limit the exploration of different coffee origins, species, processing methods, and roast profiles. They also exclude the experience and preferences of many who fall outside of these standards.

Another definition by James Hoffmann, a renowned coffee expert, describes espresso as a ‘small, strong drink made using finely ground coffee and high pressure, with the presence of crema’. Hoffmann's definition allows for flexibility and encourages creativity in espresso preparation to cater to local culture and consumer preferences.

The World Barista Championships, a pinnacle event in the coffee industry, further showcases the diversity of espresso preparation. Machine pressure is fixed; however, baristas have the freedom to choose their coffee, dose, yield, temperature, and percolation time. This freedom has led to the emergence of brighter, less developed roasts and higher yields and a vast array of novel coffee species, varieties, and processes. The focus on clarity, distinction, and novelty of flavours in the competition, is in effect, the polar opposite of the National Institute for Italian Espresso’s narrowly defined espresso concept. Yet both versions of espresso have avid fans. They are both the best standards for their respective tribes.

So, what is an espresso? It is a hot coffee beverage made with finely ground coffee, brewed under pressure (typically 6-9 bars) to create crema. Traditional espresso is served in small volumes (20-35 ml) or by weight (15-20 g). The coffee used can be a darker roast with a commoditized flavor profile, but recent trends promote showcasing the inherent flavors of the coffee through lighter roasts and experimental processing methods. Ultimately, the definition of espresso depends on the context, technology, setting, coffee, and personal preferences, reflecting the diverse experiences and preferences of espresso lovers worldwide.

As espresso continues to evolve, advancements in technology and brewing techniques offer new possibilities. Temperature profiling, automation of tamping and milk foaming, gravimetric output measurement, and precision dosing are just a few areas of ongoing innovation. With each development, the art and science of espresso continue to push boundaries, tantalizing our taste buds and inspiring coffee enthusiasts worldwide. Rest assured that wherever your taste preferences lie, there is an espresso coffee just right for you.