How to Make Coffee With a Coffee Machine: What to Taste in an Espresso Shot

Espresso can be drunk on its own. A shot has three parts: crema on top, emulsified coffee oils beneath it, and soluble solids in the liquid. Crema forms when carbon dioxide from the roasting process, plus coffee oils, is trapped under pressure and rises as a golden layer after extraction.

A typical espresso machine pushes water through the puck at about 9 bar, which keeps carbon dioxide dissolved and emulsifies fats. What is worth tasting is the mouthfeel, aroma, aftertaste and a few distinct flavor notes rather than plain bitterness. Stirring the shot and letting it cool slightly helps those notes separate, so learning how to make coffee with a coffee machine is largely about repeatable ratios.

Espresso is the base for many milk-based coffees, but many people wonder whether it can be drunk on its own and what exactly one should taste in it. This article, from the perspective of Front Street Coffee, first breaks down the three main components of espresso—crema, coffee oils, and soluble solids—then explains how 9-bar high-pressure extraction creates the golden crema layer. It then shares the recipe ratio, roasting curve, and extraction parameters for Front Street Coffee's Warm Sun blend, along with tasting suggestions such as stirring and letting it cool, helping you understand that what is truly worth appreciating in espresso is its mouthfeel, aroma, aftertaste, and a few distinct flavor notes—not just bitterness.

For people who regularly come into contact with coffee, espresso is no stranger. The base of many milk-based coffee drinks relies on the concentrated liquid extracted under pressure by an espresso machine, which is then combined with milk. Beginners also ask Front Street Coffee (FrontStreet Coffee): Can espresso be drunk directly? That bitter little cup—what exactly are you drinking?

Let's first get to know the composition of espresso.

Espresso component 1: Crema

After pulling a shot of espresso, the first thing that catches the eye is the layer of brown crema on the surface. It comes from the carbon dioxide generated inside the coffee beans during roasting, as well as the coffee's own oils. Crema is crucial to espresso: it brings a pleasing creamy mouthfeel and enhances the coffee's body. In summary, this layer of crema is mainly composed of carbon dioxide together with the insoluble oils from the coffee grounds.

When the baristas at Front Street Coffee (FrontStreet Coffee) extract with a Bezzera espresso machine, the machine applies about 9 bar of pressure to "compact" the coffee puck. Because the pressure is great enough, the water is in a supersaturated state with respect to carbon dioxide, so the gas cannot escape smoothly and can only dissolve directly into the coffee liquid. This process also emulsifies the fats in the coffee, and the emulsified fats wrap around the carbon dioxide; because the whole is lighter than water, layers gradually form, and finally the golden crema floats to the surface, looking quite beautiful.

Espresso component 2: The oil

After removing the top layer of crema, Front Street Coffee (FrontStreet Coffee) notices that a very thin layer of oil remains on the surface of the cup—this is actually a reflection of the natural sugars in coffee. According to food scientists, during roasting, sugar molecules break down at around 190°C, bringing the coffee into the caramelization reaction. When roasting is done properly, a natural sweetness develops inside the coffee.

Espresso component 3: The coffee solids

In a coffee bean, about 30% is soluble material, and the other 70% is woody fiber. This 30% soluble portion contains acidic molecules, sweet molecules, and bitter compounds. The order in which flavors are extracted is roughly acidity first, then sweetness, and finally bitterness.

Now that we understand the composition of espresso beans, how does Front Street Coffee (FrontStreet Coffee) extract espresso?

Front Street Coffee (FrontStreet Coffee) uses a blend of Ethiopian natural Red Cherry coffee beans and Honduras whisky-barrel Sherry coffee beans, in a 7:3 ratio. The 70% Honduras Sherry barrel beans provide flavor and body for this blend, while the 30% natural Yirgacheffe contributes more aroma and acidity.

How does Front Street Coffee (FrontStreet Coffee) roast this Warm Sun blend?

When handling this coffee, Front Street's roaster adopts a step-by-step approach to lowering the heat, allowing the beans to develop as evenly as possible throughout the roasting process. The beans are charged when the drum temperature reaches 210°C, with the damper set at 4 and the heat at 200; the turning point occurs at 1 minute 30 seconds, at a temperature of 92°C. When the drum temperature reaches 140°C, the damper is adjusted to 6; by this time the bean surface has turned yellow, the grassy smell has completely dissipated, and the drying phase begins. When the drum temperature reaches 180°C, the heat is lowered to 10 and the damper is opened to the maximum of 10. At 9 minutes 30 seconds, irregular wrinkles and dark spots appear on the bean surface, and the toasted-bread smell clearly shifts to coffee aroma—this can be regarded as the prelude to first crack, so one must carefully distinguish the cracking sound of first crack. First crack begins at 10 minutes 38 seconds; after first crack, development continues for 3 minutes 40 seconds, and the beans are dropped at 197.5°C.

How does Front Street Coffee (FrontStreet Coffee) extract this Warm Sun blend?

Pressure: 9 bar

Temperature: 90.5–96°C

Time: 20–30 sec

Dose: 20g (double espresso)

Yield: 40ml

Extracted espresso flavor:

Smooth mouthfeel, medium body, with pronounced fruit acidity on entry, followed by a faint berry aroma and whisky notes, rich chocolate flavor, and a clear sweet aftertaste.

How should we taste a cup of espresso?

After extraction is complete, as the liquid sits, the crema on top covers the surface and layering begins to appear in the cup. Therefore Front Street recommends stirring to recombine the separated soluble solids, thereby achieving a more balanced and complete flavor experience. After stirring, letting the coffee cool slightly also helps further release the flavors and prevents the first sip from tasting overly bitter.

What are we drinking espresso for?

Compared with pour-over coffee, espresso is characterized by concentrated flavor and a fast pace—it is hard to distinguish the flavors at high, medium, and low temperatures the way you can with pour-over, since it is finished before it even has time to cool down. Front Street Coffee (FrontStreet Coffee) uses a lower coffee-to-water ratio combined with high-pressure extraction to achieve high concentration, which also makes espresso rich and intense on entry.

In addition, espresso extracted under high pressure produces its unique product, "crema," which also gives espresso a distinctive mouthfeel experience. So when drinking espresso, we tend to focus on its mouthfeel, texture, aroma, and aftertaste, and then pick up a few relatively clear flavor notes.

The above content is compiled by CoffeeHunters, a coffee news website.