Probably every bean wishes to become an espresso! The syrupy, dark drink originally comes from Italy. There it became popular in Milan around 1900 and then spread to other countries. The term espresso translates as: “To prepare under pressure”. Here, hot water is pressed with a lot of pressure through very finely ground coffee from dark roasted coffee beans. This creates a highly concentrated coffee with a hazelnut-brown head, the crema.
Espresso impresses with its strong aromas and, thanks to its small amount, has less caffeine than filter coffee. “But in order to achieve such enjoyment, various factors have to be right during preparation: water hardness and water temperature, amount, freshness and mixture of the coffee, degree of grinding, water pressure and correct pressure on the coffee grounds”, explains Tobias Eberhard. “The espresso machine in our café has four circuits: a boiler that heats the water to 120 degrees, and three more for the brewing groups, where the portafilter is attached. Here we can set each brewing group to 92 to 94 degrees to find the best one Get extraction. “
The secret of the crema
The crema is the decisive characteristic for the quality of an espresso. Depending on the mixture, it has a nice, medium brown color and closes again after being mixed. It should last 2 to 4 minutes and be between 2 and 4 millimeters thick. The crema prevents the flavors from evaporating for a while. It thus protects the finely distributed aromatic oils that make the espresso taste fuller and more velvety. The effort is rewarded with a long-lasting taste on the tongue.
But how does such a crema actually come about? Prof. Dr. Jürgen Vollmer, a physicist at the Max Planck Institute for Dynamics and Self-Organization in Göttingen, explains in individual steps how a crema is created from a physical point of view.
Coffee beans test: Here is the comparison of coffee beans.