Latte art is a method of preparing coffee created by pouring steamed milk

Milk

Milk is a white liquid produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals before they are able to digest other types of food. Early-lactation milk contains colostrum, which carries the mother's antibodies to the baby and can reduce the risk of many...

 into a shot of espresso

Espresso

Espresso is a concentrated beverage brewed by forcing a small amount of nearly boiling water under pressure through finely ground coffee. Espresso is widely known throughout the world....

 and resulting in a pattern or design on the surface of the resulting latte

Latte

A latte is a coffee drink made with espresso and steamed milk. Variants include replacing the coffee with another drink base such as masala chai, mate or matcha...

. 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

Barista

A barista is a person, usually a coffee-house employee, who prepares and serves espresso-based coffee drinks.- Application of the title :...

 and quality of the espresso machine

Espresso machine

An espresso machine is used to produce the traditional Italian coffee beverage called espresso.-History:The first machine for making espresso was built and patented by Angelo Moriondo of Turin, Italy, who demonstrated a working example at the Turin General Exposition of 1884. He was granted patent no...

. The pour itself, then, becomes the last challenge for the latte artist.

History

Latte art developed independently in different countries, following the introduction of espresso and the development of microfoam

Microfoam

Microfoam, in coffee jargon, is a term used to describe an ideal standard for steamed milk, used for making espresso-based coffee drinks, particularly those with latte art...

, the combination of crema and microfoam allowing the pattern; it presumably was initially developed in Italy. describes pitcher-shaking in latte art as "quite standard in the world of Italian espresso preparation," indicating that it was well established in Italy by this time.

In the United States, latte art was developed in Seattle in the 1980s and 1990s, and particularly popularized by David Schomer. Schomer credits the development of microfoam ("velvet foam" or "milk texturing") to Jack Kelly of Uptown espresso in 1986, and by 1989 the heart pattern was established and a signature at Schomer's Espresso Vivace

Espresso Vivace

Espresso Vivace is a Seattle area coffee shop and roaster known internationally for its high quality of coffee and roasting practices. Baristas and coffee-bar owners have traveled from as far away as Australia and the UAE to learn from Vivace's owner, David Schomer.Schomer is known within the...

. The rosette pattern was then developed by Schomer in 1992, recreating the technique based on a photograph he saw from Cafe Mateki in Italy. Schomer subsequently popularized latte art in his course "Caffe Latte Art".

Physics

Latte art is a mixture of two colloid

Colloid

A colloid is a substance microscopically dispersed evenly throughout another substance.A colloidal system consists of two separate phases: a dispersed phase and a continuous phase . A colloidal system may be solid, liquid, or gaseous.Many familiar substances are colloids, as shown in the chart below...

s: the crema, which is an emulsion

Emulsion

An emulsion is a mixture of two or more liquids that are normally immiscible . Emulsions are part of a more general class of two-phase systems of matter called colloids. Although the terms colloid and emulsion are sometimes used interchangeably, emulsion is used when both the dispersed and the...

 (liquid-in-liquid) of coffee oil and brewed coffee (water); and the microfoam, which is a foam

Foam

-Definition:A foam is a substance that is formed by trapping gas in a liquid or solid in a divided form, i.e. by forming gas regions inside liquid regions, leading to different kinds of dispersed media...

 (air-in-liquid) of air in milk. (Milk itself is an emulsion of butterfat in water, while coffee is a solution

Solution

In chemistry, a solution is a homogeneous mixture composed of only one phase. In such a mixture, a solute is dissolved in another substance, known as a solvent. The solvent does the dissolving.- Types of solutions :...

 of coffee solids in water.) Neither of these colloids are stable

Chemical stability

Chemical stability when used in the technical sense in chemistry, means thermodynamic stability of a chemical system.Thermodynamic stability occurs when a system is in its lowest energy state, or chemical equilibrium with its environment. This may be a dynamic equilibrium, where individual atoms...

 - crema dissipates from espresso, while microfoam separates into drier foam and (liquid) milk - both degrading significantly on the order of minutes, and thus latte art lasts only briefly.

Technique

Latte art requires first producing espresso with crema and microfoam

Microfoam

Microfoam, in coffee jargon, is a term used to describe an ideal standard for steamed milk, used for making espresso-based coffee drinks, particularly those with latte art...

, 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

Contrast (vision)

Contrast is the difference in visual properties that makes an object distinguishable from other objects and the background. In visual perception of the real world, contrast is determined by the difference in the color and brightness of the object and other objects within the same field of view...

 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.

Some controversy exists within the coffee community as to whether or not there is excessive focus on latte art amongst baristas. The argument is that too much focus on the superficial

Superficial

Superficial may refer to:*Superficial , an album by Heidi Montag*"Superficial" *The Superficial, a website devoted to celebrity gossip...

 appearance of a drink leads some to ignore more important issues, such as taste. This is especially relevant with new baristas.

Styles

There are two main types of latte art - free pouring (pattern created during the pour) and etching (using a tool to create a pattern after the pour). Free pouring is far more common in American cafes, and requires little additional time in preparing a drink.

Free pouring

The two most common forms of poured latte art are a heart shape and the "rosetta" or "rosette",Both the Italianate rosetta and the Anglicized rosette are used to describe this pattern; compare doppio

Doppio

Doppio in espresso is a double shot, extracted using a double filter basket in the portafilter. This results in 60ml of drink, double the amount of a single shot espresso. More commonly called a standard double, it is a standard in judging the espresso quality in barista competitions...

and double for a double shot of espresso. also known as "fern" which resembles a type of flower or fern. Of these, hearts are simpler and more common in macchiatos, while rosettes are more complex and more common in lattes.

For free pouring, the cup is either kept level or tilted in one direction. As the milk is poured straight into the cup, the foam begins to surface on one side (due to the tilt). The barista then moves the pitcher from side to side as they level the cup, or simply wiggle the spout back and forth, and finishes by making a quick strike through the previously poured pattern. This "strike" creates the stem portion of the flower design, and bends the poured zig-zag into a flower shape.

A more direct pour and less wiggling yields a heart shape, and minor variation (reduced lobes, larger stem) yields an apple shape.

More complex patterns are possible, some requiring multiple pours.

Etching

Etched

Etching

Etching is the process of using strong acid or mordant to cut into the unprotected parts of a metal surface to create a design in intaglio in the metal...

 patterns range from simple geometric shapes to complicated drawings, such as crosshatched patterns, animals, and flowers, and are generally performed with a coffee stirrer of some sort. Etched latte art typically has a shorter lifespan than free poured latte art as the foam dissolves into the latte more quickly.

Variants

Latte art is made by adding microfoam to espresso. Similar patterns, though much fainter, can be achieved by adding microfoam to brewed coffee, as in a café au lait

Café au lait

Café au lait is a French coffee drink. The meaning of the term differs between Europe and the United States; in both cases it means some kind of coffee with hot milk added, in contrast to white coffee, which is coffee with room temperature milk or other whitener added.- Europe :In Europe, "café au...

or tea. Alternatively, patterns can be etched in the crema of an espresso, without adding any milk, in order to yield espresso art.