Latte art is a method of preparing coffee created by
pouring microfoam into a shot of espresso and resulting in a pattern or
design on the surface of the latte. It can also be created or
embellished by simply "drawing" in the top layer of foam. Latte art is
particularly difficult to create consistently, due to the demanding
conditions required of both the espresso shot and milk.
This, in turn, is limited by the experience of the barista
and quality of the espresso machine. The term also applies to other
beverages containing milk foam, such as cappuccino and hot chocolate.
Latte art developed independently in different countries, following the introduction of espresso and the development of microfoam, the combination of crema and microfoam allowing the pattern; it presumably was initially developed in Italy. Latte art requires first producing espresso with crema and microfoam, and then combining these to make latte art. See microfoam: procedure for how microfoam is made; this article concentrates on the latte art once the foam is made.
Before the milk is added, the espresso shot must have a creamy brown surface, an emulsion known as crema. As the white foam from the milk rises to meet the red/brown surface of the shot, a contrast is created and the design emerges. As the milk is poured, the foam separates from the liquid and rises to the top. If the milk and espresso shot are "just right", and the pitcher is moved during the pour, the foam will rise to create a pattern on the surface. Alternatively, a pattern may be etched with a stick after the milk has been poured, rather than during the pour.
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