Every so often interesting and exciting coffee drinks appear on coffee bar menus, and over the years this creative trend has also given rise to ever more artistic decorations on the classic cappuccino.
The ability to create latte art is one of a barista’s most impressive skills which offers a wide scope for creativity. Latte art is a fusion of two colloids and this skillful technique of preparing coffee is created by pouring microfoam into a shot of espresso, which generates a design or pattern on the surface of the latte with the brown crema (emulsion of coffee oil and brewed coffee) and the white foam. Of the two colloids neither are stable and, within seconds both significantly degrade as crema dissipates from espresso while microfoam separates into drier foam and liquid milk, thus latte art lasts only briefly.
The crema, a 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. 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. 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.
Small changes in grind size can drastically affect the taste of your final brew. For instance, if you brew coffee that is ground too coarsely ground, the water will flow through too quickly and the coffee can be under-extracted making it weak and less flavorful. However, if it is ground too fine, the coffee can be over-extracted and bitter. A coarser grind is recommended for darker roasted beans. The two main types of latte art are free pouring and etching. Free pouring is more common and requires less additional time in preparing. Commonly used motifs are the heart and rosetta of which hearts are simpler and more common in macchiatos, while rosettes are more complexed and common in lattes. Requiring multiple pours and lots of practice, more complexed patterns such as that of the tulip, wave heart and swan are possible. Creating decorative patterns with chocolate sauce using a squeeze bottle is an easy technique to try at home.
As the foam dissolves into the latte more quickly, etched latte art has a shorter lifespan than free poured latte. Generally performed with a coffee stirrer, etched patterns vary from simple geometric shapes to intricate drawings such as images of animals and flowers, and crosshatching. For coffee shops where speed is of the essence during peak times, a basic and quick method with cappuccino is to pour chocolate powder through a metal cutout in which an image, typically a flower, has been incised.
Seeing as coffee contains 98 percent water, optimum coffee water should be fresh, contain minerals and oxygen and have a low to moderate water hardness because the water quality has a great influence on the quality of the coffee.
Due to the demanding conditions of both the espresso shot and steamed milk, and limited by the experience of the barista and quality of the espresso machine, latte art can be particularly difficult to produce consistently with the pour itself, becoming the last challenge for the latte artist. The term latte is not reserved to coffee only as it also applies to other hot beverages containing milk foam such as cappuccino and hot chocolate.