Crema in the flavor and experience of Specialty Coffee

What is Crema?

Crema is a fine, golden-brown foam that appears on the surface of an espresso shot right after extraction. Experts often look at the crema to evaluate the espresso extraction because it indicates whether all parameters, such as degassing time, grind size, and pressure mechanism, were correct during extraction.

Characteristics of Crema

– Composition: Crema is made up of oils, water, and small CO2 gas bubbles. These bubbles form when hot, pressurized water is pushed through finely-ground coffee, dissolving coffee oils and releasing CO2 gas.

– Color and texture: Crema has a golden-brown color, sometimes with small dark streaks. Its texture is typically smooth and velvety, providing a soft feel on the palate.

– Role in flavor: Crema adds a distinctive flavor to espresso, with a hint of bitterness and a sweet aftertaste. It also helps retain the coffee’s aroma, enhancing the drinking experience.

Formation process

Crema forms during the espresso extraction process. James Hoffmann explains the principle of crema formation in his book, The World Atlas of Coffee, as follows: If water is under pressure, it dissolves more carbon dioxide—a gas in coffee beans created during roasting. When the brewed liquid returns to normal atmospheric pressure on its way to the cup, the liquid can no longer hold all the gas, so it escapes from the solution as countless tiny bubbles. These bubbles are trapped in the coffee liquid and appear as stable foam.

Britta Folmer, author of The Craft & Science of Coffee, emphasizes that crema cannot form without pressure, as it compresses some of the carbon dioxide in the ground coffee into the water, then slowly releases it, carrying some solids to create a thick, stable crema on the drink’s surface.

Crema is a fine, golden-brown foam that appears on the surface of an espresso shot immediately after extraction.

From this information, we can summarize the crema formation process through the following factors:

– High pressure: Espresso is brewed under high pressure, about 9 bars, through very finely ground coffee. This pressure helps extract soluble compounds and oils from coffee, facilitating the formation of crema.

– CO2 in coffee beans: When coffee is roasted, CO2 forms and is retained in the coffee beans. During espresso brewing, hot, pressurized water interacts with ground coffee, releasing CO2 and forming small gas bubbles. These bubbles contribute to the formation of crema.

– Oils and soluble compounds: Crema consists of oils and soluble compounds from coffee. These compounds are extracted under high pressure, creating a fine foam on the espresso’s surface.

– Temperature and extraction time: The ideal water temperature for espresso extraction is around 90-95°C. The extraction process typically lasts from 25 to 30 seconds. If extraction is too fast or too slow, crema quality may be affected.

Factors affecting crema stability

Once formed, the crema can lose stability due to the coalescence of nearby bubbles when the separating membrane collapses and pressure differences occur. According to Ostwald ripening, pressure differences can cause small bubbles to merge with larger ones. Ultimately, gravity forces the liquid to separate from the gas bubbles, causing the crema to thin out.

Once formed, crema can lose stability due to the coalescence of nearby bubbles when the separating membrane collapses and pressure differences occur.

Additionally, lipid content can affect crema stability. Lipids are insoluble in water and always seek to separate from it, causing continuous changes in crema. In a typical espresso shot (25ml) made from Arabica coffee, lipid content ranges from 45-146 mg—a relatively high figure. Therefore, when making espresso from Arabica coffee beans, baristas need significant skill to control crema stability effectively.

Crema can reveal a lot to baristas and consumers about espresso coffee and directly impact the tasting experience.

Crema on flavor

– Balance: Crema helps balance the flavor of espresso as it contains many soluble compounds from coffee, including acids, sugars, and oils. This reduces bitterness and creates a cup of coffee with a complex and diverse flavor profile.

– Creates a mild bitterness: Crema often carries a slight bitterness due to the soluble oils from coffee. This bitterness helps balance the sweet and sour flavors, making the overall taste of espresso more harmonious.

Crema on aroma

– Enhances aroma: Crema retains many aromatic compounds from coffee, enhancing the aroma of espresso with every sip.

– Complexity: The compounds in crema, including oils and soluble compounds, create a complex and rich aroma, offering an enticing and captivating feeling from the first lift of the coffee cup.

Crema on coffee texture

– Smoothness: Crema creates a fine and soft foam on the surface of the espresso, providing a smooth feel when drinking. This enhances the sensory experience when enjoying espresso.

– Thickness: A thick crema layer creates a dense and creamy texture when drinking espresso, making the coffee richer and more satisfying.

Crema and Coffee drinking experience:
The crema layer can enhance the coffee-drinking experience through:

– Aesthetics: Crema creates an attractive espresso with a captivating golden-brown foam. This not only provides an aesthetic appeal but also enhances the anticipation and satisfaction when enjoying coffee.

– Exciting start: When drinking espresso, the crema is the first part that touches the lips and tongue, creating an exciting and engaging initial contact for the coffee-drinking experience.

Crema helps balance the flavor of espresso because it contains many soluble compounds from coffee, including acids, sugars, and oils.

Most coffee drinkers often see crema as an indicator of a high-quality espresso. However, whether crema is a determinant of coffee quality remains an open question. Let’s examine this more closely.

Correlation between crema and coffee quality

Scott Rao, a coffee expert and author of The Coffee Roaster’s Companion, suggests that crema is not the only factor to judge coffee quality, but it is an important part of the espresso experience. He states that crema is a good indicator of proper coffee brewing, but the overall flavor of espresso is more important.

James Hoffmann, the 2007 World Barista Champion, emphasizes that although crema is an important part of espresso, it is not the sole determinant. He says: “Crema can be visually appealing, but ultimately, the overall flavor and balance of the coffee are what matter most.”

A study from the University of Trieste indicates that crema can affect the perception of coffee flavor, but it does not always accurately reflect the overall quality of coffee. The study concludes: “While crema can enhance the flavor sensation and structure of espresso, it is not the only factor determining quality.”

Expert opinions and scientific research show that crema is an indispensable part of the espresso experience. However, it should not be the sole standard for assessing coffee quality. Clearly, crema is an important factor in evaluating the quality of espresso coffee, but it is not the only determinant. It reflects the brewing process and the quality of ingredients, but the overall flavor and balance of the coffee are most important.

Crema is a good indicator that the coffee has been brewed correctly, but the overall flavor of the espresso is more important.

Espresso with crema and the Shot coffee of XLIII Coffee

At XLIII Coffee, we have discovered a new and unique approach with the Shot – a type of Specialty Coffee that removes the crema to offer a different coffee experience. So, how does it compare to regular espresso?

Crema is an important part of the traditional espresso experience. However, the coffee world is diverse and full of unique aspects yet to be explored. Therefore, XLIII Coffee is always seeking new ways to bring users closer to the authentic coffee experience.

By removing the crema layer, we want customers to focus on the pure and delicate flavor of each type of coffee we serve. Each Shot offers a fresh perspective that makes the coffee easier to drink and lighter, highlighting the natural flavors and aromas of the coffee.

The Shot at XLIII Coffee removes the crema to allow the drinker to access the pure and delicate flavors of each type of coffee more easily.

Conclusion

Crema is an important and appealing factor in the espresso world, often regarded as a symbol of quality coffee. However, when it comes to specialty coffee, flavor and experience do not solely depend on the presence of crema. Specialty coffee focuses on subtle flavors, clear origins, and meticulous processing. While crema can provide smoothness and retain aroma, it can also obscure the subtle notes that specialty coffee is known for.

At XLIII Coffee, we believe that removing the crema from the Shot helps explore and highlight the unique characteristics of each specialty coffee. This not only creates a fresh coffee-drinking experience but also allows customers to fully appreciate the subtlety and diversity of coffee flavors. Perhaps, through each tasting moment, the Shot will reveal that the flavor and experience of specialty coffee lie in the perfect combination of origin, processing methods, and more, rather than just the crema on the surface.

Come and experience the difference at XLIII Coffee with a Shot that fiercely embodies the essence of each coffee bean variety.

Question 1: What is crema in espresso coffee?

Crema is the fine, golden-brown foam that appears on the surface of an espresso shot right after extraction. It is composed of oils, water, and small CO2 gas bubbles.

Question 2: What factors affect the formation of crema?

The formation of crema depends on high pressure (around 9 bars), CO2 in the coffee beans, oils and soluble compounds from coffee, as well as the temperature and extraction time (approximately 90-95°C for 25-30 seconds).

Question 3: How does crema affect the aroma and texture of espresso?

Crema retains many aromatic compounds from coffee, enhancing the aroma of espresso. In terms of texture, crema creates a fine and soft foam on the surface, providing a smooth mouthfeel and making the cup of coffee richer.

Question 4: Why does XLIII Coffee choose to remove the crema from their coffee extractions?

XLIII Coffee removes the crema to focus on the pure and delicate flavor of each type of coffee. This makes the coffee lighter, free from the bitterness and astringency of crema, and highlights more subtle notes and flavors.

Question 5: Does crema determine the quality of coffee?

According to most experts, crema is a good indicator of coffee freshness, proper functioning of the espresso machine, and accurate extraction, but it is not the sole determinant of coffee quality. To accurately assess coffee quality, other factors such as flavor, texture, and overall sensory experience must be considered.