The Perfect Espresso - HOW TO

A compact and comprehensive guide for beginners and advanced learners.
Antonio Ardente, a gastronomy and coffee expert, originally from Naples and at home in Hamburg for 30 years, reveals his tricks and tips.

Making the perfect coffee takes time and experience – that much is clear. But what do you do if your espresso tastes too acidic or your cappuccino too watery?

Toni shows what you should pay attention to during preparation and what the possible causes of different problems are.

Toni's tips

THE BEAN

First, let's turn to the most important ingredient: the coffee beans.
There are three arch-enemies of the perfect bean – and therefore also of the perfect coffee:

pest infestation

The problem: The coffee tastes rancid and bitter. Pest infestation doesn't necessarily mean you'll find beetles in the bag. The infestation can occur as early as during cultivation, when small animals burrow unnoticed into the coffee cherries. This causes bitter substances to form even during growth, and during roasting, too much heat penetrates the interior of the bean.

The solution: High-quality coffees are carefully inspected by the roaster. This ensures that affected beans remain isolated incidents. However, if you repeatedly notice pest infestations from the same roaster, you should consider switching.

Broken beans

The problem: The coffee lacks aroma and flavor. The beans seem dry, and there's a lot of broken coffee in the bag. Broken beans are real flavor killers – they indicate insufficient moisture content in the bean as well as poor quality during harvesting, transport, and processing.

The solution: Use high-quality coffee and pay attention to the packaging. Some renowned roasters deliberately and carefully remove more moisture from their beans to create special aromas. Such coffees are usually packaged very tightly and airtight to prevent breakage.

Foreign body

The problem: You find small stones or pieces of wood among your coffee beans. This clearly indicates defects in the selection of the raw coffee and its processing – so it's no wonder the coffee doesn't taste good.

The solution: As harsh as it sounds: change your roaster! Foreign matter is an absolute no-go and indicates poor quality.

Over-roasting

The problem: The beans emit a rancid, pungent, or sour smell. This can indicate over-roasting. In this case, the heat penetrates too deeply and for too long into the bean, causing fine cracks. Oxygen enters, the bean oxidizes – resulting in unpleasant tastes and loss of aroma.

The solution: The smell test! It reveals a lot about the roast level. The aroma should never be pungent or unpleasant. If the beans crumble easily between your fingers, they have been roasted too much – then the only solution is to replace the beans.

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THE COFFEE GROUNDS

Once you've found the right roasted coffee, it's time to get to work. On its journey from bean to portafilter, the following points should be considered:

The grind

The problem: If the coffee is ground too coarsely, the water flows through it too quickly, and the coffee grounds offer too little surface area to release their aroma. The coffee becomes watery and bitter, and there is no crema.However, if it is ground too finely, excessive pressure is created in the portafilter, which releases unwanted oils – this distorts the taste.

The solution: Practice makes perfect! Experiment to find the right grind size – it varies for each type of coffee. The coffee is optimally ground when it starts to form small clumps.

The amount

The problem: If there is too little coffee in the portafilter, very little aroma can be extracted. Furthermore, the water swirls around in the portafilter and partially dissolves the coffee puck – the result is watery and tasteless. Conversely, if too much coffee grounds are used, the portafilter can come loose due to the high pressure, releasing unwanted oils.

The solution: Fill the portafilter until the coffee grounds just touch the water outlet of the machine. Many portafilters have markings or edges for this purpose.

The tamping

The problem: If the coffee grounds aren't tamped enough, the water flows through too quickly – the coffee becomes watery and bitter, and there's no crema. Tamping is an art – those who master it possess a true tool for perfect espresso.

The solution: The coffee grounds should always be evenly distributed. A so-called [method/method] can be used for this. Leveler This helps. The more evenly the coffee grounds are distributed, the more evenly the water flows through them. When tamping, ensure that sufficient pressure is applied vertically from above.

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THE EXTRACTION

We're getting closer and closer to the perfect coffee. After the correct extraction, we finally hold it in our hands. Here's what you need to keep in mind:

Preparation

The problem: The wrong cup choice or a dirty machine. A cup that's too large, such as a cappuccino cup for espresso, causes the drink to cool down too quickly and lose its aroma. Limescale deposits or dirt in the machine also lead to a bad taste.

The solution: Use the matching cups for every drinkClean your machine regularly. The water should always be clear and clean, as should the water tanks and hoses. Dirty appliances are the most common cause of bad-tasting coffee.

The temperature

The problem: If the machine is too hot, the coffee grounds burn – resulting in a bitter taste. If it's too cool, not all the aromatic compounds are released, and the coffee tastes flat.

The solution: The so-called Flushing (A short water flow without the portafilter) ensures a more even heat distribution – and rinses old coffee particles from the brewing group.
Also, pay attention to the recommended brewing temperature, which is specified for many coffees.
For Arabica beans, a brewing temperature above 90 °C is recommended; Robusta beans can tolerate slightly lower temperatures.

The water hardness

The problem: If the water is too soft, the coffee quickly tastes sour. If it's too hard, it lacks aroma and sweetness. Water hardness has a huge impact on the taste.

The solution: Test the hardness of your tap water. You can find the test kit in our product range. BWT water filter including accessories, which ensures ideal water hardness – so every coffee tastes perfect.

The amount of water

The problem: While over-extraction yields more liquid, it dilutes the aroma. The coffee loses flavor. Under-extraction is a matter of taste, but hardly affects the aroma.

The solution: Time is everything! For a true Italian espresso, an extraction time of 25 ± 5 seconds is recommended. Some roasters specify the ideal time for their coffees in their descriptions.

And there you have it – the perfect coffee.

If you follow these tips, nothing will stand in the way of true coffee enjoyment.
Now you know exactly what to check if the coffee doesn't taste as it should.