The earliest method of making Espresso was born in 1884, when an Italian named Angelo Moriondo designed a patented model of an espresso machine. The original principle of the espresso machine was to boil water in two separate boilers to produce steam, then use steam pressure to pressurize hot water (around 1.5 bar) through a bed of coffee grounds, extracting a highly concentrated coffee liquid.

However, this extraction method could not guarantee the stability of every espresso extraction. So in the early 20th century, an Italian named Luigi Bezzerra secured the espresso machine patent, redesigned and improved it, and invented a method that within a few dozen seconds pressurizes hot water to pass quickly through extremely finely ground coffee, extracting espresso directly into the cup.

He made several improvements to Moriondo's design, lowering the temperature to a range that could produce better-tasting espresso—about 94°C. He also added a coffee powder basket to achieve a filtering effect, improving the mouthfeel of the espresso. The upgraded machine was remodeled and sold commercially, and from this time on, espresso extracted quickly with steam pressure soon won the admiration and affection of people throughout Italy.

After espresso became popular in Italy, a designer named Desiderio Pavoni bought Bezzerra's patent, and the two collaborated to create a better coffee machine with a pressure valve and steam wand, which was launched at the Milan Exposition in 1906. Today, this brand is called "La Pavoni." This espresso machine design and extraction principle are what led to the method of making espresso that we now know today.

What isEspresso?

From what Front Street Coffee just shared about the working principle of the espresso machine, we can understand that espresso is made by using extremely finely ground coffee powder, then injecting 94°C hot water under pressure through the powder bed via the coffee machine to extract a highly concentrated coffee liquid.

Although it is highly concentrated, a properly extracted espresso will not taste so bitter as to make the drinker uncomfortable. Front Street Coffee believes that a good cup of espresso, though intense in flavor, will not have a burnt bitterness. The crema is delicate and smooth, the overall mouthfeel is rich and clean, and there is a distinct sweet aftertaste at the end.

After extraction is complete, espresso will have a layer of golden crema. The crema of espresso is not entirely oil; rather, it is largely carbon dioxide produced and retained within freshly roasted coffee beans due to structural changes during the roasting process.

After being ground into extremely fine particles and extracted under pressure as high as 9 bar, in a sealed and pressurized environment, the coffee bean oils and carbon dioxide merge with each other and are forced out by the water, forming a creamy foam with a delicate, smooth mouthfeel.

So if you want espresso to taste good, choose freshly roasted coffee beans of a medium-dark roast level or darker, ground and brewed on demand, so that suitable carbon dioxide can form espresso crema.

The longer coffee beans are roasted, the more carbon dioxide is retained within the beans due to continuous structural changes. But it is not the case that the more carbon dioxide, the better the espresso will taste. Too much carbon dioxide will make the crema of the espresso rough in texture and will also affect the release of soluble substances during extraction. All coffee beans sold by Front Street Coffee are shipped within 5 days after roasting is completed—100% freshly roasted.

After purchasing Front Street Coffee espresso beans, friends can first leave them unopened in a cool, dry place for 7 days after the roast completion date on the back label before starting to use them. During this period, the coffee beans will naturally release carbon dioxide, which is discharged through the one-way exhaust valve on the packaging. Releasing an appropriate amount of carbon dioxide helps achieve more stable extraction.

How to extractEspresso?

According to the Specialty Coffee Association SCA standards, use 7-9 grams (double: 14-18 grams) of coffee powder to extract 25-35g of coffee liquid in 20-30 seconds, with an extraction pressure of 9-10 bar and a water temperature of 90-96°C.

Because every coffee machine, grinder, and the coffee beans used to extract espresso are different, the coffee extraction parameters will differ to a certain degree. Therefore, you cannot rely only on the grind setting and extraction time; the most important thing is to adjust the parameters based on the final taste performance of the espresso.

Each coffee shop will adjust up or down according to the coffee beans and equipment it uses. Front Street Coffee stores use our own "Front Street Sunflower Warm Sun Blend Coffee Beans," which have a unique vanilla cream flavor. Made into an Americano, it has flavors of vanilla, cocoa, and berries. As a latte, it shows notes of vanilla cookie and milk chocolate. It can be purchased at the Front Street Tmall flagship store or the Front Street Taobao store.

Based on the daily adjustments by the baristas at the store, on the day this article was edited, 19.5g of extremely finely ground coffee powder was extracted with 94°C hot water under pressure to yield 35g of coffee liquid, with an extraction time of about 30 seconds. The espresso showed a smooth, vanilla-cream-like texture, slight berry sweetness and acidity, fermented wine aroma, and the sweet fragrance of hazelnut caramel.

EspressoHow to drink it?

Compared with the strong, bitter taste of espresso more than a decade ago, coffee bean quality has been continuously improving today, and everyone has done more research on coffee roasting, so the quality of espresso has now also improved.

Before tasting, we first take a sip of ice water to clean the mouth and cause the muscles of the tongue surface to contract slightly. After the barista serves the espresso, you can stir the coffee with a spoon to make it more uniform overall. Then taste it in three sips. The first sip is to taste the flavors, the second sip to feel the richness, and the third sip to sense the sweet aftertaste and lingering finish.

What coffee beans are suitable for espresso?

"Front Street Specialty Blend Coffee Beans" 75 yuan/454g: Colombian washed coffee beans + Brazilian semi-washed coffee beans, with flavor notes of nuts, dark chocolate, and caramel.

"Front Street Commercial Blend Coffee Beans" 60 yuan/454g: Robusta washed coffee beans + Colombian washed coffee beans + Brazilian semi-washed coffee, with flavor notes of nuts, cocoa, and caramel.

"Front Street Basic Blend Coffee Beans" 50 yuan/454g: Yunnan washed small-bean coffee + Brazilian semi-washed coffee beans, with flavor notes of soft fruit acidity, caramel, and nuts.

"Front Street Classic Blend Coffee Beans" 33 yuan/100g; Brazilian semi-washed coffee beans + Indonesian Mandheling coffee beans + Vietnamese coffee beans, with rich crema and a full-bodied mouthfeel;

"Front Street Strawberry Candy Espresso" 43 yuan/100g; Costa Rican coffee beans + Panamanian coffee beans + Ethiopian coffee beans, with aromas of roses, strawberry candy, and glucose, a prominent fruity sweet-tartness, and a pleasant taste.

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