Discover the best tips for espresso

The perfect espresso

Various factors are decisive in the preparation of a perfect espresso, such as the freshness of the coffee, the type of bean, the grind, the amount of coffee, the water hardness, the brewing temperature, the pressure and the throughput time.

It is best to always grind the coffee beans fresh, as ground coffee loses its flavour after a short time. The water temperature for a perfect brew is between 90°C and 96°C, depending on the type of coffee, and many espresso machines have a standard brewing temperature of 93°C. To prepare a classic espresso on a portafilter machine, we recommend a coffee powder to liquid ratio of 1:2. Perfect extraction produces a wonderful espresso with a dense, hazelnut-brown crema.

Preheating the espresso machine

Set the espresso machine at least 15 minutes before use to ensure that all water-bearing components of the machine are at the correct temperature and the necessary pressure. As certain parts only heat up properly during espresso preparation, you can also insert the portafilter without coffee into the brew group and let some water run through.

In addition, almost every espresso machine has a tray for cups on the top of the machine. To prevent your espresso from cooling down straight away, it is recommended that you place your cups on the machine shelf to preheat them.

The choice of coffee beans

There are basically two types of coffee: Robusta (Coffea canephora) and Arabica (Coffea arabica). In contrast to Robusta, Arabica contains a higher proportion of coffee oils and is generally considered to be more aromatic, less bitter and softer. It is also regarded as the higher quality bean due to the higher number of chromosomes. However, Robusta beans form a thicker, longer-lasting crema due to the lower proportion of coffee oils and also contain more caffeine than Arabica beans. This is why Arabica-Robusta blends are very popular for a classic espresso from a portafilter machine

The grind

Finding the right grind is crucial for the success of a perfect espresso. If the coffee is ground too finely, the coffee will drip very slowly and become bitter. If the coffee is ground too coarsely, the coffee runs through very quickly and can be acidic. As numerous factors such as temperature, humidity, air pressure, quality, blend and degree of roast of the beans are important for the end result, there is no "one and only" right grind. The ideal grind is when the desired coffee powder/liquid ratio is achieved for a given extraction time of 20 to 30 seconds and an aromatic espresso with a dense hazelnut-brown crema is produced.

The dosage

The amount of coffee you pour into the portafilter depends on the size of the portafilter. The sieve should not be overfilled or underfilled and the pressed coffee should be just below the edge of the sieve support. For a classic espresso, a ratio of 1:2 is considered ideal, i.e. 9 grams of coffee for a result of 18ml espresso in the cup with a single sieve or 18 grams of coffee powder for two 18ml espressos or a double espresso with a double sieve.

The "roping"

The coffee powder is pressed with a tamper, also known as a coffee tamper or espresso tamper, to provide the necessary resistance to the water flowing through. It is particularly important that you press the coffee powder evenly to ensure constant extraction. The best way to do this is to support the portafilter so that its sieve is horizontal in space and the tamper can be pressed straight down into the portafilter, then wipe off the coffee residue and you are ready for the actual preparation.

Brewing

Before inserting the portafilter into the brew group, briefly run water through the brew group to loosen any residue on the shower filter of the brew group and to drain off any overheated water. Then insert the portafilter into the brew group and let the water run for 20 to 30 seconds. On some portafilter machines, you can push the portafilter lever upwards to start the water flow and downwards to stop it after 20 to 30 seconds. With other machines, this is done at the touch of a button.

The result

Ultimately, the truth is always in the cup. With a perfect extraction with the portafilter machine, this is a wonderfully fragrant, delicious-tasting espresso with a beautiful hazelnut-coloured crema. Don't forget: Your coffee loses flavour with every contact with oxygen. It is therefore important that you close the coffee packet tightly after making coffee. This is easily done with a packaging clip.

How can you recognise over- and under-extraction?

The art of brewing a perfect coffee lies in finding the balance between over- and under-extraction and at the same time achieving the desired strength. Grind size and dosage are two easily adjustable parameters that influence flavour and body.

Under-extraction: If the coffee is ground too coarsely, the coffee flows through more quickly and fewer components can be released from the coffee. The result is therefore rather weak in flavour and watery, with a light crema. In addition, the fruity and acidic notes of the coffee are particularly noticeable, as the bitter substances are dissolved at the end of the extraction process. If a coffee contains a lot of fruit acid on its own, under-extraction is therefore not recommended. Over-extraction: A grind that is too fine leads to over-extraction. The fine powder offers greater resistance to the water and bitter and tannins are unintentionally released on the way into the cup. As a result, the coffee tastes bitter and its crema is dark and thin.

The amount of coffee has an influence on the strength of the drink. The proportion of dissolved coffee particles in a filter coffee is significantly lower than in an espresso. Accordingly, an espresso smells and tastes more intense or even stronger. The strength of an espresso can be regulated simply by the amount of coffee powder.

Troubleshooting

Why is the coffee sour?

• Too coarse a grind: If the grind is too coarse, the coffee can taste too acidic and watery, as under-extraction mainly dissolves the acidic rather than the bitter substances.
• Brewing temperature too low: If your coffee machine is not preheated enough, fewer flavourings can be released from the coffee, making it watery and sour.
• Light roast: Light roasts are often used to make filter coffee and still contain a wonderful natural fruit acidity that has not been completely broken down during the roasting process. It may well be that you find a lightly roasted Kenyan Arabica coffee prepared as an espresso to be sour and prefer a chocolaty, nutty variety from Brazil.
• Acidic water: The main component of an espresso is water and therefore the water has a major influence on the flavour of your coffee. If the pH value of your water is well below 7, your coffee will be acidic.

Why is the coffee bitter?

• Too fine a grind: A fine grind results in a longer extraction time and therefore more bitter substances are released from the coffee.
• Brewing temperature too high: If the coffee is brewed at too high a temperature, more bitter and tannins can be released, making the espresso in the cup more bitter.
• Dark roast: The darker the coffee is roasted, the more bitter the espresso will be.
• High Robusta content: Arabica-Robusta blends are often roasted dark in the Italian style and these are often more bitter with their dark roast.
• Cleaning your coffee machine: If the coffee machine and grinder are not cleaned sufficiently, coffee oils can build up and give the fresh coffee a rancid, bitter flavour. So make sure you clean your coffee equipment regularly.