What defines espresso within coffee culture?

Espresso is coffee extracted quickly at high temperature under pressure, and its two defining traits are crema and concentration. Crema is the golden foam on top, formed as carbon dioxide escapes the brewed liquid; a thick, dense layer usually means the beans were freshly roasted. A dark crema color generally points to a darker roast and a fuller mouthfeel.

Concentration comes from fine, even grinding and roughly nine atmospheres of pressure pushing near-boiling water through the puck in a few dozen seconds, dissolving a large share of soluble material. If no crema appears, the beans may be old or the shot sat too long. As coffee culture spreads, shops vary the beans and recipe, so flavor differs from bar to bar.

As coffee culture sweeps across the country, coffee shops are gradually popping up on every street and alley, and Italian-style coffee, known for being quick and convenient, is especially popular. A rich, aromatic espresso gives rise to all kinds of popular Italian-style coffees, and Front Street is here to talk about the characteristics of espresso, the “soul” of the coffee shop.

Main characteristics of espresso

Espresso, also called Espresso, is a coffee liquid extracted quickly at high temperature by Italians using a pressure-boosted coffee machine, with a layer of golden foam floating on the surface. Each shop uses different Italian-style coffee beans and different extraction recipes, so the flavor varies, but a standard espresso has the following two characteristics.

Cream

When we order an espresso at a coffee shop and the barista brings it over right after extraction, you can see a thick layer of golden foam floating on top, which we call Crema.

Coffee beans produce a large amount of gas during roasting, and water dissolves out the carbon dioxide under high pressure, but as the brewed coffee gradually returns to normal atmospheric pressure, the coffee liquid can no longer trap all the gas components, so countless small bubbles emerge from the liquid. These bubbles remain on the surface of the coffee, looking like a stable layer of “bubbles.” A rich, dense Crema means the coffee beans used for the espresso were freshly roasted. Because the gas inside coffee beans continuously escapes over time, the longer it has been since the roast date, the lower the carbon dioxide content, and the thinner the foam layer during extraction.

If an espresso has no Crema on top, it is very likely the coffee beans have been stored too long, or perhaps the espresso was made and left too long before drinking, so the foam disappeared. The darker the color of the Crema, the richer the flavor usually is. Because coffee beans undergo the Maillard reaction at high temperatures, darker-roasted coffee beans produce a darker foam layer and a thicker mouthfeel.

High concentration

Extracting a single espresso requires releasing a large amount of soluble substances in just a few dozen seconds, so the coffee grounds need to be ground very finely and evenly. After near-boiling hot water and 9 atmospheres of high pressure, the concentration of espresso is very high, all the flavors are doubled and concentrated, and the first sip presents a powerful mouthfeel. After swallowing, various aromas linger in the mouth with a long finish. Therefore, many coffee shops serve a glass of water alongside a strong espresso for guests.

How to make espresso

Many coffee enthusiasts unknowingly equip their homes with all kinds of coffee gear, and friends obsessed with Italian-style coffee even stock up on espresso machines, ready to extract it themselves. Here at Front Street, using shop-made Italian-style coffee as a reference, let’s briefly explain how to make an Espresso.

The coffee machine at Front Street’s shop is the commercial single-group “Lelit Bianca,” which can adjust extraction by changing the pressure, with a maximum pressure of 11 bar. A home coffee machine only needs to reach 9 bar of pressure to meet the functions of extraction and milk frothing, paired with an Italian-style coffee grinder.

Front Street uses the capacity of a double basket, with a dose of about 18–20 grams, and Front Street uses 20 grams of coffee grounds when making drinks. Usually the ratio of coffee grounds to coffee liquid is between 1:1.5 and 1:2.5. Front Street’s extraction ratio is 1:2, that is, 20 grams of coffee grounds extract 40 grams of coffee liquid. Time is related to the flow rate of the coffee grounds; generally a single extraction is controlled within 20–35 seconds, because under 20 seconds the coffee usually tastes thin, while over 35 seconds it is easy to over-extract and develop a burnt, bitter taste. Most of Front Street’s espressos fall within the range of 28–30 seconds.

Front Street first wipes the basket dry, turns on the grinder, grinds a double dose of coffee grounds, places it on an electronic scale to adjust up or down until it reaches 20 grams. Then use a tool to distribute the grounds evenly and tamp the coffee puck firmly to ensure more stable extraction. Then turn on the extraction switch to release water, wetting the brewing head while washing away the coffee grounds stuck to it, gently lock the portafilter onto the brewing head, and start the extraction. When the electronic scale shows 40 grams of coffee liquid extracted, at about 30 seconds, you can pull down the extraction switch. Pour the coffee liquid into an Espresso cup and enjoy.

The taste and mouthfeel of Espresso are related to the coffee beans used. The Italian-style coffee made at Front Street’s shop uses Front Street Sunflower Warm Sun Blend. It is composed of Honduras Sherry coffee and Ethiopia natural Red Cherry in a 7:3 blend. Made into Espresso, it has rich crema, a very obvious whiskey aroma, an entry of vanilla cookies and berry acidity, a solid flavor, and after drinking, the whole mouth is filled with various aromas.

Espresso can also be diluted with water, which is the Americano commonly seen on menus, fragrant and overflowing, and when milk is added it becomes a latte, presenting the sweet deliciousness of chocolate and cream.

Italian-style blend coffee bean recommendations

In addition to the Warm Sun Blend with a wine aroma profile, Front Street’s bean list also has three cost-effective Italian-style blend coffee beans for everyone to choose from. The espresso extracted mainly presents nutty notes, and because each blend uses a different ratio, each has subtle differences.

1. Classic rich type — Front Street Commercial Blend Coffee Beans

Washed Robusta coffee beans (10%) + washed Colombia coffee beans (30%) + semi-washed Brazil coffee (60%)

The resulting espresso has rich golden crema and a nutty aroma. When tasting, there is a toasty coffee bitterness, but accompanied by more of a creamy, full mouthfeel, and after swallowing, the bitterness fades away, leaving fragrance on the lips and teeth.

2. Slightly acidic rich type — Front Street Dark Cocoa Blend Coffee Beans

Washed Yunnan small-bean coffee beans (30%) + semi-washed Brazil coffee beans (70%)

The soft acidity of Yunnan small-bean coffee paired with the rich aroma of Brazil Cerrado coffee gives the espresso a taste of caramel, nuts, and gentle plum acidity.

3. Balanced rich-aroma type — Front Street Specialty Blend Coffee Beans

Washed Colombia coffee beans (30%) + semi-washed Brazil coffee beans (70%)

Adding Colombia coffee to the nutty notes of classic Brazil coffee, the espresso presents a dark chocolate flavor, caramel sweetness, and a full roasted aroma.

Finally, if you want the extracted Italian-style coffee to present the various flavors described by Front Street, Front Street recommends choosing freshly roasted coffee beans. After roasting, coffee beans need a 7–10 day degassing stage, then enter the fragrant peak-flavor period, when the extracted espresso is more stable. To ensure everyone can drink freshly roasted coffee beans when ordering, the coffee beans shipped by Front Street are all freshly roasted within 5 days, so when you receive them they are still at the stage of rich aroma.

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