Espresso

Espresso is a coffee brewing system and the beverage produced by that system. The beverage is the base for many popular coffee drinks (see "Recipes & Presentations" section). The Italian word "Espresso" means "speed" or "to put under pressure", defining the espresso brewing process. It may also suggest a single cup made "expressly for" a consumer as opposed to a pot of coffee made for a group.

In 1855 at the Paris Exposition, Edouard Loysel de la Lantais introduced a very large hydrostatic percolator that used the pressure of steam in a boiler to raise the brewing water through a tube. Some cite this as the first espresso machine. However, in the late 1930's and 40's, Giovanni Gaggia developed a spring-lever brewing head assembly that product espresso, a coffee beverage that was distinctly different from any other brewed coffee. The Gaggia invention produced a single serving of espresso with an intense, sweet coffee flavor and aroma, and "creme" in about 15 seconds.¹

It is easy to visually identify a correctly brewed cup of espresso by the thick, golden brown foam - the creme - that floats on top of the brew and clings to the side of the cup. You will also see striped variations it is color; the stripes are called "tigre" (after the stripes of a tiger).

The brewing head assembly where the espresso is produced, is called a group. There are one-group, two-group, three-group and four-group machines. Each group will brew one, two or three 1.5 ounce-demitasse servings at a time.

The Roast

Coffee destined for use in an espresso brewer is generally roasted darker than American Roast. The beans must be thoroughly roasted; a dark surface color is not a guarantee of adequate roasting. Insufficient roasting imparts a green, grassy taste and over-roasting causes a burnt, bitter flavor. Regional preference may influence the roast, but the aim is to produce the full bodied, smooth, sweet flavor of espresso. In Italy where espresso was refined, the further south you travel, the darker the roast color. On the island of Sicily a very dark roast is preferred; in the Southern portion of mainland Italy, the roast is also very dark, but lighter than on Sicily; and the Northern Italians prefer a more moderately roasted espresso coffee.

The Grind

For correct extraction of the espresso blend, use finely ground coffee from fresh beans and gently tamp them in the filter. Too fine a grind will produce a bitter brew, and too coarse a grind will produce a watery brew. If the coffee is not fresh or ground correctly, the creme (which comes from the fat content of the coffee) will be absent, and the beverage will look and taste flat. Freshness is so important to the result that most espresso is ground within minutes of brewing.

Bulk density of the ground coffee is also important. Since the ambient temperature and humidity of the coffee will affect the softness or brittleness of the bean, the grind setting may require adjustment by the skilled barista during the day.

The Brewing Process

There are several commercial types of espresso brewers: manually operated (piston-style), semi-automatic, automatic and fully automatic brewers. To brew a single cup of espresso, use 7 grams of finely ground coffee. In all types of espresso brewers except the fully automatic, gently tamp the coffee into the pre-heated filter. Wipe any coffee grounds from the rim of the porta-filter and lock the porta-filter into the group. (The fully automatic will do this for you.)

Within the brewer, fresh water is heated separately from the machine's main reservoir. The fresh water is heated to 194° F when in contact with the coffee, and forced through the coffee with pressure in excess of 100 pounds per square inch. Some brewers have an external gauge which registers the pressure in the boiler. When the gauge shows the pressure between .6 and .8 bar, there is adequate pressure to produce 194° F water. The pressurized water makes almost instant contact with every grain of ground coffee. The process is completed in approximately 25 seconds and produces 1.5 ounces of 185° F espresso.

The Manual Espresso Brewer

As the name suggests, manual machines require the most involvement of the operator. The whole bean coffee grinder is separate from the espresso brewer so grind selection, proper measuring and tamping of the coffee in the filter are in the hands of the operator. The operator of the manual brewer begins the brewing cycle and chooses when to end the cycle by operating a lever which is directly connected to an internal piston. These choices are critical and require skill and experience. In addition to controlling the extraction time of the brew cycle; the operator hydraulically initiates the flow of water through the ground coffee. The operator must be attentive since the force of the pressurized water is directly in his hands as he controls the lever. The lever requires a sure grip because the back pressure is great. Lastly, when the brew cycle is completed using a manual brewer, the operator must dispose of the spent grounds by tapping the porta-filter into a knock box until the pack is dislodged, and then rinse the filter.

The Semi-Automatic Espresso Brewer

A semi-automatic machine is similar; the grinder is separate from the brewer, the measuring and tamping are manual. However, the semi-automatic espresso brewer has an electric pump which pressurizes the flow of water through the grounds, and "on-off" buttons to begin the brewing cycle. The operator still must initiate the brewing and choose when to end the cycle; but a semi-automatic brewer is safer, easier to operate and there is less margin for error in the brew cycle than in a manual brewer. At the end of the cycle, the operator empties the grounds into a knock box.

The Automatic Espresso Brewer

Again, the grinder is separate from the brewer. The grinding, measuring and tamping of the coffee in the filter still require experience and skill since they are manual operations. The brewing begins and ends with the touch of a button. The water flow in an automatic espresso brewer is controlled by an electronic flow metering device which automatically shuts off the machine at the end of the brew cycle. The brew cycle of an automatic brewer is easier and more consistent than either a manual or semi-automatic espresso brewer. The operator disposes of the coffee grounds in the same manner as with a manual or semi-automatic espresso brewer.

The Fully Automatic Espresso Brewer

A fully automatic machine performs all the functions internally at the push of a button, reducing the requirement of skilled, experienced operators. The automatic espresso machine grinds and tamps the coffee, starts and ends the brew cycle, and eliminates the grounds from the filter - all with the push of a button.

In the foodservice industry, the operators and distributors who are new to the world of espresso often ignore the distinctions between a semi-automatic, automatic, and the fully automatic espresso brewer, and refer to all as "automatic" or "fully automatic". Indeed, they are very similar, but are distinctions that the buyer should be cognizant of when choosing the type of brewer best suited to his operation, budget and staff. If an automatic brewer is the type you want, examine the method of ending the brew cycle to be sure that an automatic brewer is what you get.

To produce most espresso-based beverages the espresso brewer should be equipped with a steaming arm. Steamed milk and/or the foam from steamed milk are essential elements to the presentation of a Cappuccino, a Caffé Latte, or a Café au Lait. The steaming arm infuses pressurized steam into cold milk, heating and foaming it. The amount of pressure an espresso machine can produce will be reflected in the quality and the texture of the foam. The more powerful machines will provide better results.

There are espresso brewers available with systems to steam milk automatically. The stored milk is refrigerated, then flows through the brewer to a steaming chamber. The hot, steamed milk then goes through a faucet to be added to the coffee drink. Unless there is a flushing system to clean the milk line between the refrigeration and the faucet after each use, this is risky business. As every foodservice operator knows, milk products are highly susceptible to bacterial growth within any warm environment. An espresso brewer provides an ideal environment. We recommend using fresh cold milk in a clean steaming pitcher, and frequent cleansing of the steam arm and nozzle, or a system that cleans the milk line between uses.

Espresso Recipes & Presentations

Espresso: 1.5 ounces of espresso beverage, served in a demitasse (a 3-ounce cup). It's often served with a sugar cube on the side. Any beverage that deviates from this has another name.

Cappuccino: A serving of espresso with the foam of steamed milk, served in a cappuccino (6 ounce) cup. The foam, when placed on top of the espresso creme, will have a brown halo. Cappuccino is 1/3 espresso, 2/3 dense foam of steamed milk. Cappuccino is a traditionally served with a sugar cube on the side.

The Italian Caffé Latte and the French Café au Lait are made of strong full-bodied coffee and hot milk poured simultaneously into a 6-8 oz. bowl or wide mouth cup, served with a sugar cube on the side. It is the most popular breakfast coffee in France and Italy. In the United States, a Caffé Latte (or Caffé Latte Americano) is a serving of espresso with equal volumes of steamed milk and foam of steamed milk served in a 6-8 oz. cup, mug or tall glass. It is also served with a sugar cube on the side. These are the foundation of the popular espresso drinks served in the United States; and there are many non-traditional variations, made with whipped cream, hot chocolate, low-fat milk, flavored syrups, etc. For instance, Caffé Mocha is a serving of espresso blended with hot chocolate, topped with whipped cream and served in a tall mug.

Steamed Milk for Espresso Drinks

The steam that collects in the top of the brewer tank of an espresso machine is used to heat and foam milk for espresso drinks. A valve controls the flow of steam through the steam arm to the nozzle.

Before you start the milk-steaming process, direct the steam arm and nozzle into the drip tray. Open the steam valve to purge any water that may be resting in the tip of the steam arm; then close the steam valve.

Start always with cold, fresh milk in a clean stainless steel steaming pitcher. The steaming arm nozzle is placed into the milk, the valve opened and the steam heats and foams the milk.

Immerse approximately half an inch of the steam arm nozzle into the steam pitcher half filled with fresh, cold milk and fully open the valve to start heating the milk. As the steam causes the milk to become warm and a frothy head of foam forms, the surface of the milk will rise. As the foam forms, lower the pitcher so that the nozzle is continually about half an inch below the surface of the milk.

Steamed milk is finished at about 160-165°F. Be careful not to scald the milk. Turn off the steam valve before the heat of the milk makes the pitcher too hot to the touch. When done skillfully, the foam will be slightly aerated but dense and creamy, similar in texture to light meringue, and the milk will be heated. This will produce the dense foam desired for a Cappuccino, and the hot milk to Caffé Latte or Café au Lait.

Purge the steam arm with a short blast of steam and clean the steam arm and nozzle well after each use to remove any milk residue.

The densest foam is produced from whole milk, although any type of milk can be used. In the United States, skim or low-fat milks produce what is termed a "skinny" cappuccino, latte or au lait.

Espresso Equipment Maintenance

As with all coffee, clean brewing equipment is essential for espresso. The filter, porta-filter, spray head and gasket within the group will accumulate coffee grounds and coffee oils if not cleaned properly and often. Water flow and coffee extraction may be impeded, affecting not only the coffee flavor but potentially overloading the pump with back-pressure. Follow the manufacturer's recommended daily and weekly cleaning procedures for both the espresso machine and the whole bean coffee grinder.

Proper installation, maintenance and repair of espresso equipment, and employee training are necessary to brewing good espresso. Choose a supplier who will provide no less than these essential services.

1. Ian Bersten; Coffee Floats, Tea Sinks, Helian Books, Roseville, Australia, 1993; pages 81-83, 115-117, 260.


Origin to Cup - Espresso - Sustainability - Seven Steps - Brewing Guide - Brewing Systems - Perfect Cup
	Origin to Cup Espresso Sustainability Seven Steps Brewing Guide Brewing Systems The Perfect Cup Newsletter	Home: Coffee: Espresso Espresso is a coffee brewing system and the beverage produced by that system. The beverage is the base for many popular coffee drinks (see "Recipes & Presentations" section). The Italian word "Espresso" means "speed" or "to put under pressure", defining the espresso brewing process. It may also suggest a single cup made "expressly for" a consumer as opposed to a pot of coffee made for a group. In 1855 at the Paris Exposition, Edouard Loysel de la Lantais introduced a very large hydrostatic percolator that used the pressure of steam in a boiler to raise the brewing water through a tube. Some cite this as the first espresso machine. However, in the late 1930's and 40's, Giovanni Gaggia developed a spring-lever brewing head assembly that product espresso, a coffee beverage that was distinctly different from any other brewed coffee. The Gaggia invention produced a single serving of espresso with an intense, sweet coffee flavor and aroma, and "creme" in about 15 seconds.¹ It is easy to visually identify a correctly brewed cup of espresso by the thick, golden brown foam - the creme - that floats on top of the brew and clings to the side of the cup. You will also see striped variations it is color; the stripes are called "tigre" (after the stripes of a tiger). The brewing head assembly where the espresso is produced, is called a group. There are one-group, two-group, three-group and four-group machines. Each group will brew one, two or three 1.5 ounce-demitasse servings at a time. The Roast Coffee destined for use in an espresso brewer is generally roasted darker than American Roast. The beans must be thoroughly roasted; a dark surface color is not a guarantee of adequate roasting. Insufficient roasting imparts a green, grassy taste and over-roasting causes a burnt, bitter flavor. Regional preference may influence the roast, but the aim is to produce the full bodied, smooth, sweet flavor of espresso. In Italy where espresso was refined, the further south you travel, the darker the roast color. On the island of Sicily a very dark roast is preferred; in the Southern portion of mainland Italy, the roast is also very dark, but lighter than on Sicily; and the Northern Italians prefer a more moderately roasted espresso coffee. The Grind For correct extraction of the espresso blend, use finely ground coffee from fresh beans and gently tamp them in the filter. Too fine a grind will produce a bitter brew, and too coarse a grind will produce a watery brew. If the coffee is not fresh or ground correctly, the creme (which comes from the fat content of the coffee) will be absent, and the beverage will look and taste flat. Freshness is so important to the result that most espresso is ground within minutes of brewing. Bulk density of the ground coffee is also important. Since the ambient temperature and humidity of the coffee will affect the softness or brittleness of the bean, the grind setting may require adjustment by the skilled barista during the day. The Brewing Process There are several commercial types of espresso brewers: manually operated (piston-style), semi-automatic, automatic and fully automatic brewers. To brew a single cup of espresso, use 7 grams of finely ground coffee. In all types of espresso brewers except the fully automatic, gently tamp the coffee into the pre-heated filter. Wipe any coffee grounds from the rim of the porta-filter and lock the porta-filter into the group. (The fully automatic will do this for you.) Within the brewer, fresh water is heated separately from the machine's main reservoir. The fresh water is heated to 194° F when in contact with the coffee, and forced through the coffee with pressure in excess of 100 pounds per square inch. Some brewers have an external gauge which registers the pressure in the boiler. When the gauge shows the pressure between .6 and .8 bar, there is adequate pressure to produce 194° F water. The pressurized water makes almost instant contact with every grain of ground coffee. The process is completed in approximately 25 seconds and produces 1.5 ounces of 185° F espresso. The Manual Espresso Brewer As the name suggests, manual machines require the most involvement of the operator. The whole bean coffee grinder is separate from the espresso brewer so grind selection, proper measuring and tamping of the coffee in the filter are in the hands of the operator. The operator of the manual brewer begins the brewing cycle and chooses when to end the cycle by operating a lever which is directly connected to an internal piston. These choices are critical and require skill and experience. In addition to controlling the extraction time of the brew cycle; the operator hydraulically initiates the flow of water through the ground coffee. The operator must be attentive since the force of the pressurized water is directly in his hands as he controls the lever. The lever requires a sure grip because the back pressure is great. Lastly, when the brew cycle is completed using a manual brewer, the operator must dispose of the spent grounds by tapping the porta-filter into a knock box until the pack is dislodged, and then rinse the filter. The Semi-Automatic Espresso Brewer A semi-automatic machine is similar; the grinder is separate from the brewer, the measuring and tamping are manual. However, the semi-automatic espresso brewer has an electric pump which pressurizes the flow of water through the grounds, and "on-off" buttons to begin the brewing cycle. The operator still must initiate the brewing and choose when to end the cycle; but a semi-automatic brewer is safer, easier to operate and there is less margin for error in the brew cycle than in a manual brewer. At the end of the cycle, the operator empties the grounds into a knock box. The Automatic Espresso Brewer Again, the grinder is separate from the brewer. The grinding, measuring and tamping of the coffee in the filter still require experience and skill since they are manual operations. The brewing begins and ends with the touch of a button. The water flow in an automatic espresso brewer is controlled by an electronic flow metering device which automatically shuts off the machine at the end of the brew cycle. The brew cycle of an automatic brewer is easier and more consistent than either a manual or semi-automatic espresso brewer. The operator disposes of the coffee grounds in the same manner as with a manual or semi-automatic espresso brewer. The Fully Automatic Espresso Brewer A fully automatic machine performs all the functions internally at the push of a button, reducing the requirement of skilled, experienced operators. The automatic espresso machine grinds and tamps the coffee, starts and ends the brew cycle, and eliminates the grounds from the filter - all with the push of a button. In the foodservice industry, the operators and distributors who are new to the world of espresso often ignore the distinctions between a semi-automatic, automatic, and the fully automatic espresso brewer, and refer to all as "automatic" or "fully automatic". Indeed, they are very similar, but are distinctions that the buyer should be cognizant of when choosing the type of brewer best suited to his operation, budget and staff. If an automatic brewer is the type you want, examine the method of ending the brew cycle to be sure that an automatic brewer is what you get. To produce most espresso-based beverages the espresso brewer should be equipped with a steaming arm. Steamed milk and/or the foam from steamed milk are essential elements to the presentation of a Cappuccino, a Caffé Latte, or a Café au Lait. The steaming arm infuses pressurized steam into cold milk, heating and foaming it. The amount of pressure an espresso machine can produce will be reflected in the quality and the texture of the foam. The more powerful machines will provide better results. There are espresso brewers available with systems to steam milk automatically. The stored milk is refrigerated, then flows through the brewer to a steaming chamber. The hot, steamed milk then goes through a faucet to be added to the coffee drink. Unless there is a flushing system to clean the milk line between the refrigeration and the faucet after each use, this is risky business. As every foodservice operator knows, milk products are highly susceptible to bacterial growth within any warm environment. An espresso brewer provides an ideal environment. We recommend using fresh cold milk in a clean steaming pitcher, and frequent cleansing of the steam arm and nozzle, or a system that cleans the milk line between uses. Espresso Recipes & Presentations Espresso: 1.5 ounces of espresso beverage, served in a demitasse (a 3-ounce cup). It's often served with a sugar cube on the side. Any beverage that deviates from this has another name. Cappuccino: A serving of espresso with the foam of steamed milk, served in a cappuccino (6 ounce) cup. The foam, when placed on top of the espresso creme, will have a brown halo. Cappuccino is 1/3 espresso, 2/3 dense foam of steamed milk. Cappuccino is a traditionally served with a sugar cube on the side. The Italian Caffé Latte and the French Café au Lait are made of strong full-bodied coffee and hot milk poured simultaneously into a 6-8 oz. bowl or wide mouth cup, served with a sugar cube on the side. It is the most popular breakfast coffee in France and Italy. In the United States, a Caffé Latte (or Caffé Latte Americano) is a serving of espresso with equal volumes of steamed milk and foam of steamed milk served in a 6-8 oz. cup, mug or tall glass. It is also served with a sugar cube on the side. These are the foundation of the popular espresso drinks served in the United States; and there are many non-traditional variations, made with whipped cream, hot chocolate, low-fat milk, flavored syrups, etc. For instance, Caffé Mocha is a serving of espresso blended with hot chocolate, topped with whipped cream and served in a tall mug. Steamed Milk for Espresso Drinks The steam that collects in the top of the brewer tank of an espresso machine is used to heat and foam milk for espresso drinks. A valve controls the flow of steam through the steam arm to the nozzle. Before you start the milk-steaming process, direct the steam arm and nozzle into the drip tray. Open the steam valve to purge any water that may be resting in the tip of the steam arm; then close the steam valve. Start always with cold, fresh milk in a clean stainless steel steaming pitcher. The steaming arm nozzle is placed into the milk, the valve opened and the steam heats and foams the milk. Immerse approximately half an inch of the steam arm nozzle into the steam pitcher half filled with fresh, cold milk and fully open the valve to start heating the milk. As the steam causes the milk to become warm and a frothy head of foam forms, the surface of the milk will rise. As the foam forms, lower the pitcher so that the nozzle is continually about half an inch below the surface of the milk. Steamed milk is finished at about 160-165°F. Be careful not to scald the milk. Turn off the steam valve before the heat of the milk makes the pitcher too hot to the touch. When done skillfully, the foam will be slightly aerated but dense and creamy, similar in texture to light meringue, and the milk will be heated. This will produce the dense foam desired for a Cappuccino, and the hot milk to Caffé Latte or Café au Lait. Purge the steam arm with a short blast of steam and clean the steam arm and nozzle well after each use to remove any milk residue. The densest foam is produced from whole milk, although any type of milk can be used. In the United States, skim or low-fat milks produce what is termed a "skinny" cappuccino, latte or au lait. Espresso Equipment Maintenance As with all coffee, clean brewing equipment is essential for espresso. The filter, porta-filter, spray head and gasket within the group will accumulate coffee grounds and coffee oils if not cleaned properly and often. Water flow and coffee extraction may be impeded, affecting not only the coffee flavor but potentially overloading the pump with back-pressure. Follow the manufacturer's recommended daily and weekly cleaning procedures for both the espresso machine and the whole bean coffee grinder. Proper installation, maintenance and repair of espresso equipment, and employee training are necessary to brewing good espresso. Choose a supplier who will provide no less than these essential services. 1. Ian Bersten; Coffee Floats, Tea Sinks, Helian Books, Roseville, Australia, 1993; pages 81-83, 115-117, 260.
Shop ][ News ][ About Boyds ][ Brands ][ About Coffee ][ Business ][ At Home ][ Contact © 2007 Boyd Coffee Company. Buy Boyds Products Online