espresso
Espresso [ ˌɛspʀɛso ] is one of Milan originating Kaffeezubereitungsart , in hot water with high pressure through very finely ground coffee is pressed from roasted coffee beans.
The process results in a concentrated coffee on which there is a thick, hazelnut-brown foam layer - the crema - which adds to its aroma. Due to the strong roast , the ground coffee for espresso contains less caffeine than an equal amount of ground coffee for filter coffee. Correspondingly, with the typical portion sizes, the amount of caffeine per cup of espresso is lower than per cup of filter coffee. Only the concentration of caffeine is higher, as less water is used in the preparation (typically 25 ml water for espresso, but 125 ml for filter coffee). In addition, due to its predominant fat solubility, caffeine is less washed out during the approx. 25 seconds of espresso preparation than when standing in the coffee filter for a longer period of time or when preparing other types of preparation in which there is contact between the coffee grounds and water for minutes.
Espresso is served in small, thick-walled and preheated cups with a capacity of around 40 ml. It is drunk sweetened or unsweetened and often served with a glass of water.
Espresso is the most common way of making coffee in southern Europe, especially in Italy , Spain , Portugal and France . In these countries you get an espresso when you order coffee : Italian caffè , French café , Spanish café , Portuguese café , Greek καφές , Bulgarian кафе , Croatian kava .
In Switzerland , espresso is usually prepared, in German-speaking Switzerland most often as espresso lungo ( German café crème : extended, coffee), in western Switzerland as normal espresso.
Origin and Etymology
Espresso has its roots in Italy, where this type of coffee preparation appeared in Milan around 1900. There, before other methods were introduced, it was prepared exclusively with steam and only served at the counter in bars.
The name espresso goes back to so-called "coffee locomotives" manufactured between 1840 and 1870. Their name alludes to the analogy of preparing coffee with steam and a steam locomotive . The Milanese Luigi Bezzera was able to fall back on the popularity of the association of coffee with steam-powered express trains when he patented the first machine for caffè espresso in 1901 . The word espresso is therefore a borrowing from English, where the term express for express train has been used since the middle of the 19th century.
In different language areas is espresso written with "x", such as in Spain ( café expreso ), Portugal ( cafe expresso ) and Romania ( cafea expres ).
The espresso bean
Espresso is usually based on darker roasted mixtures - often with a slightly higher proportion of Robusta . Due to the dark roast, the beans largely lose their palpable acids - much more so than with the lighter roasted filter coffee. This is intentional because the high pressure preparation method means that the acid dissolves disproportionately quickly. An espresso drink based on light ground coffee has a noticeable acidity. This apparent contradiction to traditional espresso can, however, also be aimed at consciously: light espresso roasts with fruity notes have been in trend for some time.
As the degree of roasting increases, there is also a shift in the bitterness profile. While in the course of roasting (light to medium degrees of roasting) "soft" bitter elements are initially formed, these are largely broken down again in darker roasting samples and "harsh" bitter elements are increasingly dominant.
Robusta beans are considered to be less aromatic than Arabica , but bring a fuller body to the espresso drink and thus create the typical heaviness of espresso. In addition, it is much easier to create a good crema with a Robusta component than with an espresso made from a pure Arabica blend.
Quality criteria
Ultimately, the quality of an espresso does not only depend on the mixing ratio. Traditionally, there are five criteria to be met to prepare a good espresso (the 5M formula ):
- The mix - the choice of coffee beans ,
- Quality of beans
- Careful roasting that goes well with the beans
- Freshness of the beans used
- The amount - the right amount of powder (usually 7 g),
- The degree of grinding, also: the grinder - the correct, not too coarse, not too fine grinding of the beans,
- The machine - a good machine,
- Temperature of the water
- Pressure of water
- Quality (including degree of hardness) of the water
- The person - the maker of the drink.
- Sensitive pressing according to the degree of grinding (= pressing the coffee grounds into the sieve)
- Correctly selected (thick-walled and preheated) cup, otherwise the espresso will cool down quickly
- Coordination of all factors
The “island sample” is a quality test that is easy to carry out. When sprinkling sugar into the espresso, a "sugar island" must form, which only gradually disappears. If this is not the case, the espresso has too little crema or a crema that is too poor in consistency.
Roasting
The roasting process turns the natural product into the raw material. The beans lose water up to 150 ° C, from 160 ° C roasting begins, during which a large number of chemical reactions take place. Up to 12 liters of CO 2 are produced per kilogram of beans . At temperatures of 160 ° C to 240 ° C, due to the relatively thick cell walls, this gas leads to an overpressure of up to 25 bar in the cells and the desired processes take place. Above all, the amino acids and the simple sugars ( galactose , glucose , arabinose and sucrose ) react and trigonelline and chlorogenic acids are broken down, and lipids and caffeine are hardly changed. For espresso, darker roasted varieties are preferred because the content of astringent- tasting chlorogenic acids is lower and the degradation products of the trigonelline enhance the roasted aroma. In addition, the vitamin nicotinic acid (niacin, vitamin B3) is created and a good espresso can cover 15% of the daily requirement.
Grind
During the roasting process, decarboxylation takes place and the resulting CO 2 in the bean is a protective gas for the aroma substances , which are protected from oxidation by the oxygen in the air, but an espresso with freshly ground beans tastes more aromatic. The mechanical crushing by grinding facilitates the extraction of the dark color pigments and the aromatic substances. An unsuitable grinding can lead to the grinding stock being heated up to 100 ° C, so that an unsuitable grinder can reduce the quality of the espresso. The grain size for espresso should be 0.3 mm to 0.4 mm, for example for filter coffee 0.4 mm to 0.6 mm are sufficient. A broad grain size distribution is better for the subsequent process and an optimal flow time than a homogeneous powder.
extraction
To get the espresso ready to drink, it is extracted with hot water in the third stage. Many years of experience of professional baristas give the following optimal parameters: 3.5 cm sieve radius, 30 ml water, 6.5 ± 1.5 g coffee powder, pressed in the sieve with around 200 N (approx. 20 kP), at a pressure of 9 ± 2 bar and a temperature of 90 ± 5 ° C. During extraction, water first flows through dry powder, so that a constant volume velocity with the dripping drink only occurs after a few seconds, which is why the grain size distribution is important. A well-sized machine should make a cup of espresso in 30 ± 5 seconds. During this time, only 75% of the caffeine is dissolved, but undesirable ingredients and flavors are avoided in the short time. The lipids remaining in the beans during roasting are melted by hot water and form an emulsion with droplets between 0.5 µm and 10 µm between the coffee particles. In this emulsion, the aromatic substances can dissolve and remain in the hot liquid without evaporating. However, the amount of fat in an espresso remains relatively small at around 1 g.
Espresso machine
The espresso machine was developed by a Neapolitan - who allegedly was annoyed about the slowness of coffee preparation - in collaboration with the Milanese engineer Luigi Bezzera. Bezzera is considered to be the inventor of the espresso machine. While the prototype was presented at the World Exhibition in Paris in 1855 , the first series production of Bezzera did not go to stores in Italy until 1901 and soon all over the world.
Despite its name, espresso cannot be prepared in an espresso pot ("moka"). Without a pumping mechanism, either the required pressure cannot be achieved (only up to 1.5 bar ) or the temperature becomes too high. One of the classics among espresso pots is the Moka Express model designed by Alfonso Bialetti in 1933 , which is produced in its almost original form and can be found in many households around the world.
technology
A portafilter espresso machine is required to prepare a good creamy espresso. In this, 88 ° C to 94 ° C hot water at an initial pressure of about 9 bar is pressed through very finely ground coffee, which was previously filled into the sieve of the portafilter and spread over the entire surface and pressed down. The processing time should be around 25 seconds, in which 7–9 grams of ground coffee are used to produce around 25 ml of espresso. If the right amount of water runs through the machine faster, the espresso will be bland and sour. If the water runs through the coffee grounds for too long, on the other hand, too many bitter substances dissolve. The throughput time is mainly influenced by the grind of the coffee grounds and the brewing pressure of the machine, the pressure of the coffee grounds on the sieve, the number and size of holes in the sieve and the amount of coffee powder.
machinery
A distinction is made between the following designs for espresso machines.
- Hand lever machines
- They are sometimes, but not necessarily, preloaded with a strong spring that pushes the water through a piston and the portafilter; however, the pressure can also be generated manually with a hand lever and thus the foaming can be regulated (Pavoni); Typically they are made of solid brass , copper and chrome and have a nostalgic design.
- Semiautomatic
- differ from lever machines in that they have a built-in pump (often a vibration pump, rotary pump with a fixed water connection) that generates the pressure; Typically, in many household machines only the brewing vessel and the housing are made of solid metal, whereas plastic hoses are used for the lines and feeders.
- Fully automatic machines
- are machines with a complete preparation system consisting of a grinder, tamper container, membranes and pumps that remove beans from a container, grind, press and brew; They typically do not have a visible portafilter and are made almost entirely of plastic, with the exception of visible parts, and have a modern, technical design with switches or buttons and LC or LED displays.
In addition, a distinction is made between single-circuit and dual-circuit machines .
- With single-circlers, there is only one waterway and the temperature has to be switched between brewing water and steam, which leads to waiting times due to heating or cooling.
- Dual circuits, on the other hand, each have their own circuit for steam and brewing water. In this way, brewing water and steam for frothing milk can be drawn off at the same time.
Espresso grinder
Another technical component of importance for the quality of espresso is the grinder. Special requirements are placed on the espresso grinder .
Not only must it be able to grind the beans particularly finely, but the flour must also have a particularly uniform grain size. Coffee grinders or beating mechanisms are not suitable for preparing espresso flour. The high demands on precision explain the high prices for espresso grinders. If you brew an espresso from flour whose particles are unevenly large, two scenarios are conceivable: If the brewing process is tailored to the small particles, the aromas of the thicker particles are not optimally dissolved and do not get into the espresso. If, on the other hand, the process is tailored to the larger particles, undesirable bitter substances that affect the taste of the coffee are released from the small particles towards the end of the brewing process.
Pressino
The quality is created during pressing, that is, pressing the coffee grounds into the portafilter with the help of a stamp- shaped "coffee tamper " ( it. Pressino , en. Tamper ). So that the throughput time is around 25 seconds, the grinding degree is coarser with stronger contact pressure and finer with less contact pressure.
Typical values
The Istituto Nazionale Espresso Italiano ( National Institute for Italian Espresso ) recommends the following criteria:
- required amount of ground coffee = 7 g ± 0.5 g
- Water temperature at the outlet of the unit = 88 ° C ± 2 ° C
- Beverage temperature in the cup = 67 ° C ± 3 ° C
- Water inlet pressure = 9 bar ± 1 bar
- Processing time = 25 seconds ± 5 seconds
- Viscosity at 45 ° C> 1.5 mPas
- Total fat content> 2 mg / ml
- Caffeine <100 mg / cup
- Volume in the cup (including crema) = 25 ml ± 2.5 ml
Another laboratory gives as an ideal preparation:
- Quantity of espresso beans: 6.95 g
- Particle size for espresso extraction: ≈200–250 µm
- Water temperature: 92 ° C
- Water input pressure: 9.3 bar
- Processing time: 25 s
Error in preparation
| error | root cause | ||
|---|---|---|---|
| taste | |||
| Bitter taste | Brewing temperature too high, beans ground too finely or too compressed, processing time too long, too much ground coffee, too much pressure | ||
| Sour taste | Too acidic water, too low brewing temperature, beans too coarsely ground, too soft water, too light roast, too short processing time, wrong type of coffee (filter coffee roasting instead of espresso roasting) | ||
| Foreign taste | bad bean quality, beans covered, chlorinated water, wrong type of coffee | ||
| Too little flavor | Too little ground coffee, too old coffee, beans too coarsely ground or not compressed enough, too much water | ||
| Crema | |||
| Not enough crema | Beans too coarsely ground or not compressed enough, coffee too old, cup or machine dirty | ||
| Crema too dark | Beans ground too finely or roasted too much, brewing temperature too high | ||
| Crema too light | Beans too old or ground too coarsely or not compressed enough, brewing temperature too low | ||
| Crema does not have a stand | Cup too cold or too hot, water pressure too low | ||
The correct setting of the grinder determines the extraction:
- If the coffee bean is ground finer, more substances are extracted overall.
- If the setting is too fine, the contact time of the hot water is too long and excessive bitter substances are extracted. The crema also disappears again.
The variation in the degree of grinding causes a much greater change in the result than the compression of the coffee grounds in the portafilter. The influence, such as the variation in the degree of grinding, can be achieved by varying the pressure of the ground coffee in the portafilter.
Variations
Italian variations
Espresso variations
Mixture and the names in the respective countries:
- 7 g coffee + 25 ml water = Portuguese Bica , Spanish café solo , Italian caffè , German espresso , in Italy this is what is understood as espresso in Germany .
- 7 g coffee + 25 ml water + cool and stir = Italian Granita di Caffè ( granita = finely crushed: frozen espresso) Stirring prevents the formation of ice blocks. Espresso crystals are formed.
- 7 g coffee + 25 ml water + water and sugar + ice cold = Italian Caffè freddo : strongly sweetened and ice-cold espresso extended with water. It is usually only served in Italian bars in the summer months.
- 7 g coffee + 25 ml water + 25–50 ml hot water = Italian caffè americano : An espresso is subsequently mixed with the same or double the amount of hot water. If the espresso is poured onto the water in reverse order so that the crema is retained, this is also called Long Black .
Other quantities:
- 7 g coffee + 15 ml water = Portuguese Italiana , Italian caffè ristretto , German espresso ristretto , ristretto = narrow, limited: a very concentrated and therefore strong espresso (smaller amount of water: 15 ml).
- 7 g coffee + 50 ml water = Portuguese Bica cheia , Italian caffè lungo , German espresso lungo , lungo = long: An extended espresso with twice the amount of water for the same amount of coffee is called espresso lungo .
- 14 g coffee + 50 ml water = Portuguese Bica dupla , Italian Caffè doppio , German Double espresso doppio = double: twice the amount of espresso, i.e. H. 50 ml.
- 14 g coffee + 30 ml water = Portuguese Bica dupla curta , Italian Ristretto doppio , German Double ristretto : twice the amount of a ristretto, effectively an espresso prepared with twice as much coffee powder.
Espresso with different ingredients
With spirits
7 g coffee + 25 ml water + spirits = Portuguese café com cheirinho , Italian Caffè corretto : Caffè corretto (also espresso corretto): an “improved” coffee that is “corrected” with spirits, usually with a shot of grappa .
With ice cream
Affogato , usually with a scoop of vanilla ice cream, occasionally with other types of milk ice cream, such as nut or chocolate ice cream.
With little milk
- 7 g coffee + 25 ml water + small sip of frothed milk = Italian caffè macchiato caldo or macchiato , sometimes espresso macchiato caldo ( German warmly stained espresso ). In Italy, espresso is often poured with a small sip of milk foam to refine it. The (Caffè / Espresso) Macchiato Caldo is often topped with a small cap of frothed milk.
- 7 g coffee + 25 ml water + small sip of cold milk = Portuguese Bica pingada , Italian Caffè macchiato freddo : also espresso macchiato freddo. The Macchiato Freddo is "stained" with a small sip of cold (fresh) milk.
With more milk
- Cappuccino : The well-known cappuccino consists of an espresso to which frothed milk is added. After a short time, the foam layer will settle on top. The name of the cappuccino is probably derived from the Capuchins . It alludes to the brown habit of the capuchin ( Italian cappuccini ) in connection with the milk froth hood.
- Latte macchiato ( German spotted milk ): is an Italian children's drink, which consists almost exclusively of warm milk with a little espresso mixed in. In Germany, a modified form has developed under this name. This consists of three layers: a bottom layer of hot milk (2/3), a top layer of foamed milk (1/3) and an espresso, which is carefully poured through the milk foam (using the back of a spoon). Since the cooler, fatty milk has a higher density than the hot espresso, the coffee floats on the milk. In the case of plant-based milk substitutes, yeast and soy components promote foaming and buoyancy.
- Caffè Latte : A milk coffee that is often drunk at home for breakfast and is usually served in a bowl. At home, it is not made with classic espresso, but with coffee from a moka pot , which is filled with hot milk. Milk foam is rarely used as well.
With chocolate or cocoa
- Marocchino: The real marocchino is prepared with a teaspoon of chocolate, espresso, milk foam and pure cocoa powder. The melted chocolate is spread on the inside of the glass with circular movements and poured with an espresso. Two to three teaspoons of milk foam are then dusted with plenty of cocoa powder.
- Bicerin: is a variant of espresso from Turin and consists of equal parts espresso and hot chocolate. The finish is a hood made of lightly whipped cream.
Portuguese variations
- Bica: Corresponds to the simple espresso.
- Garoto: Espresso and milk in roughly equal parts, is served in an espresso cup
- Cafe Pingado: Corresponds to the espresso with a drop of milk.
- Italiana: Corresponds to a short espresso.
- Galão and Meia de leite: Correspond to a milk coffee or cappuccino.
Spanish variations
- Café solo ( Spanish solo: alone ): corresponds to a simple espresso
- Café cortado or mostly just: Cortado ( Spanish cortado: shortened, sheared, cut ): In this Spanish variant, the espresso is also drunk with little milk, but with more than with "espresso macchiato".
- Cortado leche leche: Canarian specialty, like Cafe cortado with the additional use of a sweetened cream made from condensed milk. Served in a glass.
- Café Bombón: Sweetened condensed milk in a glass and an espresso on top , also known as “Cortado con leche condensada”.
- Carajillo : In Spain it used to be a tradition among workers to drink an espresso with aniseed liqueur in the morning before work. Like the Cortado , this Carajillo is not drunk from cups, but from small, heat-resistant glasses. In Spanish bars, carajillo is usually understood to mean an espresso with Spanish brandy .
- Café con hielo ( Spanish con hielo: with ice cream ) or Café del tiempo ( Spanish for coffee of the season ): If you order a café con hielo in Spain , you get a normal espresso cup and an additional glass filled with ice cubes. If necessary, the espresso is sweetened and poured into the glass with the ice cubes and drunk.
- Romano (South American / Spanish): Espresso + 1 small slice of lemon
- Barraquito: This Canarian specialty consists of sweetened condensed milk, a dash of orange liqueur, and a lemon zest. The espresso is then topped up so that the liquids do not mix. A milk cap is placed on top and dusted with a little cinnamon powder.
More variations
In particular, American coffee house chains such as Starbucks brought numerous new creations onto the market, often in variations with milk and syrups of various flavors. Often an attempt is made to arouse Italian associations through the naming:
- Caffè moca: This variant consists of 1/3 espresso, 2/3 hot milk and 1–2 tablespoons chocolate syrup or liquid chocolate, plus a cap of milk foam or cream. Usually the caffè moca is served in a tall glass
- Micro moca: This variant consists of 1/2 espresso, 1/2 hot milk and 1/2 teaspoon cocoa or liquid chocolate, plus a cap of milk foam or cream, the micro moca is served in an espresso cup
Price peculiarities in Italy
- Price “al banco”: In Italy, the respective municipality sets the maximum price of an espresso at the bar (“al banco”: “while standing” at the counter). This is a maximum of one euro ten cents throughout Italy .
- “Coperto” price: A service fee (“coperto”) is only added if you take your espresso while sitting at the table and, at special tourist locations such as St. Mark's Square in Venice, an expected fee for the live music.
- Voluntary Social Prize Sospeso (German: Aufgehobener) Espresso with social added value, i.e. an espresso for a good cause. The Sospeso is based on the Neapolitan tradition of helping. If you've had a successful day or just want to make a social contribution, you have a sospeso, you have an espresso and you pay two. Those who cannot afford espresso themselves can ask for this “canceled” and drink it for free. People who are badly off can participate in social life.
Espresso aphorism
An aphorism about coffee attributed to the French politician Charles-Maurice de Talleyrand-Périgord has entered the general vocabulary to describe a good espresso: " It has to be hot as hell, black as the devil, pure as an angel and sweet as love ".
See also
literature
- Ernesto Illy: From the bean to the espresso. In: Spectrum of Science . May 2003, pp. 82-87.
- Francesco Illy, Riccardo Illy : Coffee, from beans to espresso. Droemer Knaur, Munich 1994, ISBN 3-426-26763-2 .
- Ingrid Niemeier, Jost Niemeier: Espresso, from A to Z, from the little black dress and everything that goes with it. Heel, Königswinter 2002, ISBN 3-89880-104-7 .
- Karl Petzke, Sara Slavin, Carolyn Miller, Jennifer Morla, Sandra Cook: Espresso. Culture and cuisine. With photos by Karl Petzke (original title: Espresso , translated by Gitta Mohrdieck). Hädecke Verlag, Weil der Stadt 2005, ISBN 3-7750-0449-1 .
Web links
- Istituto Nazionale Espresso Italiano
- Good Coffee FAQ
- Coffeeright - Everything you need to know about coffee and espresso
- coffeescience.org Information site of the National Coffee Association of USA
Individual evidence
- ↑ italian-beans.com: Italian roasting processes for espresso beans
- ↑ kaffee.org: Caffeine content of coffee - A comparison
- ↑ Coffee trends in Switzerland, Germany and Austria. ( Memento from January 28, 2016 in the Internet Archive )
- ↑ Bezzera. Retrieved January 3, 2020 .
- ↑ Jeffrey T. Schnapp: The Romance of Caffeine and Aluminum . In: Critical Inquiry . No. 28 , 2001, p. 250 .
- ↑ Duden newsletter. from March 19, 2010.
- ↑ Light roasted coffee is the trend - manager magazin . In: manager magazin . ( manager-magazin.de [accessed on October 28, 2016]).
- ↑ Simone Blumberg, Oliver Frank, Thomas Hofmann: Quantitative Studies on the Influence of the Bean Roasting Parameters and Hot Water Percolation on the Concentrations of Bitter Compounds in Coffee Brew . In: Journal of Agricultural and Food Chemistry . tape 58 , no. 6 , March 24, 2010, ISSN 0021-8561 , p. 3720-3728 , doi : 10.1021 / jf9044606 .
- ^ Ernesto Illy, Luciano Navarini: Neglected Food Bubbles: The Espresso Coffee Foam . In: Food Biophysics . tape 6 , no. 3 , March 30, 2011, ISSN 1557-1858 , p. 335-348 , doi : 10.1007 / s11483-011-9220-5 , PMID 21892345 , PMC 3140933 (free full text) - ( springer.com [accessed October 28, 2016]).
- ↑ The Five Elements for Good Espresso ( Memento from October 7, 2014 in the Internet Archive )
- ↑ a b c Klaus Roth : Espresso: A three-step preparation. In: GIT Labor-Fachzeitschrift. Issue 8, 2013, p. 486 ff.
- ↑ https://patents.google.com/patent/US726793?oq=%22Luigi+Bezzera%22 Abr. Nov 2019
- ↑ a b This brewing pressure, i.e. the pressure that is built up during the extraction, should not be confused with the maximum possible pump pressure. In the advertising of household espresso machines, the pump pressure of the built-in vibration pump of 15 bar is often given as a quality feature, so that the layperson has the impression that this is the necessary brewing pressure to prepare an espresso. If you were to prepare an espresso with 15 bar brewing pressure, it would be pretty inedible. The brewing pressure applied can be set on the machine (using a bypass valve), but is usually already correctly preset in household machines. For a schematic explanation see Jim Schulman (English).
- ^ Istituto Nazionale Espresso Italiano: The Certified Italian Espresso and Cappuccino. (PDF; 1.3 MB)
- ↑ lastampa.it: Il caffè passa a 1 euro e 10. I baristi: “Rincari dovuti all'aumento delle tasse”