The secret of a perfect crema
The coffee machine is naturally also an important factor in making a coffee or espresso crowned with a perfect crema. However, apart from the coffee machine, other factors are decisive for making a “Schümlikaffee” as it is called in Switzerland:
The crema, the thick, golden-brown foam which is formed on the prepared espresso, is made up of oils, proteins and different types of sugar, and contains a major part of the espresso aroma.
Coffee blend decisive:
The more oils a coffee blend contains, the less stable the crema. For this reason espresso coffee blends often contain a certain percentage of Robusta beans, as these beans only contain around 10 percent oil in comparison to the quality, highly-aromatic Arabica beans, which contain around 16 percent.
Clean cups:
If the espresso cups are not clean and if they have grease residues on the insides, the crema will also collapse more quickly due to the lowered surface tension.
