Coffee preparation

Main article: Coffee

Coffee preparation is the process of turning coffee beans into a beverage. The particular steps needed vary with the type of coffee desired, and with the raw material being worked with (e.g., pre-ground vs. whole bean).

The agricultural and industrial processes for producing whole roasted coffee beans is typically referred to as coffee processing.

Grinding

An old-fashioned manual coffee grinder.

The fineness of the grounds has a major impact on the brewing process, and matching the consistency of the grind with the brewing method is critical to extracting the optimal amount of flavor from the roasted beans. Brewing methods which expose coffee grounds to heated water for a longer duration require a coarser grind than faster brewing methods. Beans which are too finely ground for the brewing method in which they are used will expose too much surface area to the heated water and produce a bitter, harsh, "over-extracted" taste. At the other extreme, an overly coarse grind will produce a weak, watery, under-flavored result.

The rate of deterioration increases when the coffee is ground, as a result of the greater surface area exposed to oxygen. With the rise of coffee as a gourmet beverage, it has become much more popular to grind the beans at home before brewing, and there are many home appliances available which are dedicated to the process.

There are three methods of producing coffee grounds ready for brewing.

Burr-grinding

A picture showing the hopper and burrs on a Zassenhaus manual coffee grinder.

This method is burr-based with two revolving elements crushing or "tearing" the bean and with less risk of burning. Burr grinders can be either wheel or conical; the latter are quieter and are less likely to clog. Burr grinders "mill" the coffee to a reasonably consistent size, which produces a more even extraction when brewed.

• Conical burr grinders preserve the most aroma and produce very fine and consistent grounds. The intricate design of the steel burrs allows a high gear reduction to slow down the grinding speed. The slower the speed, the less heat is imparted to the ground coffee, thus preserving maximum amount of aroma. Because of the wide range of grind settings, these grinders are ideal for all kinds of coffee equipment: espresso, drip, percolators, French press. Better conical burr grinders can also grind extra fine for the preparation of Turkish coffee. Grinding speed is generally below 500 rpm.
• Burr grinders with disk-type burrs usually grind at a faster speed than conical burr grinders and as a result tend to create a bit more warmth in the coffee. They are the most economical way of getting a consistent grind in a wide range of applications. They are well suited for most home coffee preparation.

Chopping

Most modern "grinders" actually chop the bean into pieces (and some coffee drinkers merely use a home blender to do the job). Although enjoying a much longer life before wearing out the blades, the result is dramatically less effective in producing a homogeneous grind and, therefore, will create a degraded product in the cup.

Blade grinders “smash” the beans with a blade at very high speed (20,000 to 30,000 rpm). The ground coffee has larger and smaller particles and is warmer than ground coffee from burr grinders. Blade grinders create “coffee dust” which can clog up sieves in espresso machines and French presses. These grinders are (in theory) only suitable for drip coffee makers though even here the product is inferior as a result. They also can do a great job for grinding spices and herbs. They are not recommended for use with pump espresso machines.

Pounding

Turkish coffee is produced by infusion with grounds of almost powdery fineness. In the absence of a sufficiently high-quality burr grinder, the only reliable way to achieve this is to pound the beans in a mortar and pestle.

Brewing

Coffee can be brewed in several different ways, but these methods fall into four main groups depending upon how the water is introduced to the coffee grounds. If the method allows the water to pass only once through the grounds, the resulting brew will contain mainly the more soluble components (including caffeine), whereas if the water is repeatedly cycled through the beans (as with the common percolator), the brew will contain more of the relatively less soluble compounds found in the bean; as these tend to be more bitter, that type of process is less favored by coffee aficionados.

Coffee in all these forms is made with coffee grounds (coffee beans that have been roasted and ground) and hot water, the grounds either remaining behind or being filtered out of the cup or jug after the main soluble compounds have been removed. The fineness of the grind required differs by the method of extraction.

Water temperature is crucial to the proper extraction of flavor from the ground coffee. The recommended brewing temperature of coffee is 93 °C (199.4 °F). Any cooler and some of the solubles that make up the flavor will not be extracted. If the water is too hot, some undesirable elements will be extracted, adversely affecting the taste, especially in bitterness.

The usual ratio of coffee to water for the style of coffee most prevalent in Europe, America, and other Westernized nations (evident in publications such as textbooks on coffee and instruction manuals for drip-brew machines) is between one and two tablespoons of ground coffee per six ounces (180 millilitres) of water; the full two tablespoons per six ounces tends to be recommended by experienced coffee lovers. Note that the size of the grinds has an effect on the strength and the amount of coffee needed and may need to be adjusted accordingly.

Brewed coffee continually heated will deteriorate rapidly in flavor; even at room temperature, deterioration will occur. For this reason aficionados frown upon the hotplate which is sometimes used to keep brewed coffee warm prior to serving. However, if it is kept in an oxygen-free environment it can last almost indefinitely at room temperature, and sealed containers of brewed coffee are sometimes commercially available in food stores in America or Europe, with Frappuccino being commonly available at convenience stores and grocery stores in the United States.

Electronic coffee makers boil the water and brew the infusion with little human assistance and sometimes according to a timer. Some even grind the beans automatically before brewing.

Boiling

Despite the name, care should be taken not to actually boil the coffee (or at least not for too long) because that would make it bitter.

• The simplest method is to put the ground coffee in a cup, pour in hot water and let it cool while the grounds to sink to the bottom. This is a traditional method for making a cup of coffee that is still used in parts of Indonesia. This method (known as "mud coffee" in the Middle East owing to an extremely fine grind that results in a mud-like sludge at the bottom of the cup) allows for extremely simple preparation, but the drinker must be careful if they want to avoid drinking grounds either from this layer or floating at the surface of the coffee (which can be avoided by dribbling cold water onto the 'floaters' from the back of a spoon). If the coffee beans are not ground finely enough, the grounds do not sink.

• Turkish coffee was a very early method of making coffee and is still used in the Middle East, North Africa, East Africa, Turkey, Greece, and the Balkans. Water is placed all together with very finely ground coffee in a narrow-topped pot, called an ibrik (Arabic), cezve (Turkish), kanaka (Egyptian), briki (Greek), or džezva (Štokavian), and allowed to briefly come to the boil. It is usually drunk sweet, in which case sugar is added to the pot and boiled with the coffee; it is also often flavored with cardamom, mostly in Arab countries. The result is imbibed in small cups of very strong coffee with foam on the top and a thick layer of sludgy grounds at the bottom of the cup, "telve" in Turkish, and often referred to in English as the "mud".

• "Cowboy coffee" is made by simply heating coarse grounds with water in a pot, letting the grounds settle and pouring off the liquid to drink, sometimes filtering it to remove fine grounds. While the name suggests that this method was derived from or used by cowboys, presumably on the trail around a campfire, it is also seen among others who do not drink coffee frequently and/or lack any specialized equipment for brewing. Some coffee aficionados actually prefer this method. In Finland and Norway, which have the highest consumption of coffee per-capita [1], this is the traditional way to make coffee.

Pressure

• Espresso is made with hot water at between 91 °C (195 °F) and 96 °C (204 °F) forced, under a pressure of between eight and nine atmospheres (800–900 kPa), through a lightly packed matrix (called a puck) of finely ground coffee. It can be served alone (often after an evening meal), and is the basis for many coffee drinks. It is one of the strongest tasting forms of coffee regularly consumed, with a distinctive flavor and crema, a layer of emulsified oils in the form of a colloidal foam standing over the liquid.

A rare form of a moka pot (the upper section formed as a coffee fountain).

• A moka pot , also known as "Italian coffeepot" is a three-chamber design which boils water in the lower section and forces the boiling water through the separated coffee grounds in the middle section. The resultant coffee (almost espresso strength, yet without the crema) is collected in the upper section. It usually sits directly on a heater or stove. Some models feature a glass or plastic top to view the coffee as it is forced up.
• The Aeropress is a recently popularized device similar to the French Press. Hot water is poured into a ground coffee mixture, but the coffee is pressed out under moderate pressure a relatively short time later through a paper microfilter, without accumulating the considerable amounts of bitter sediment associated with a French Press.
• Various types of single-serving coffee machines force hot water under pressure through a coffee pod composed of finely ground coffee sandwiched between two layers of filter paper or a propriatary capsule containing ground coffee. Examples include the pod-based Senseo and Home Café systems and the proprietary Tassimo and K-Cup systems.

Gravity

• Drip brew (also known as filter or American coffee) is made by letting hot water drip onto coffee grounds held in a coffee filter (paper or perforated metal). Strength varies according to the ratio of water to coffee and the fineness of the grind, but is typically weaker than espresso, though the final product contains more caffeine. By convention, regular coffee brewed by this method is served in a brown or black pot (or a pot with a brown or black handle), while decaffeinated coffee is served in an orange pot (or a pot with an orange handle).
• The common electric percolator — which was in almost universal use in the United States prior to the 1970s, and is still popular in some households today — differs from the pressure percolator described above. It uses the pressure of the boiling water to force it to a chamber above the grounds, but relies on gravity to pass the water down through the grounds, where it then repeats the process until shut off by an internal timer. The coffee produced is held in low esteem by some coffee aficionados because of this multiple-pass process. Many coffee drinkers still prefer gravity percolation because they claim it delivers a richer cup of coffee in comparison to drip brewing.
• Another variation is cold-brewed coffee, sometimes known as "cold press." Cold water is poured over coffee grounds and allowed to steep for eight to twenty-four hours. The coffee is then filtered, usually through a very thick filter, removing all particles. This process produces a very strong concentrate which can be stored in a refrigerated, airtight container for up to eight weeks. The coffee can then be prepared for drinking by adding hot water to the concentrate at an approximately 3:1 ratio (water to concentrate), but can be adjusted to the drinker's preference. The coffee prepared by this method is very low-acid with a smooth taste, and is often preferred by those with sensitive stomachs. Others, however, feel this method strips coffee of its bold favor and character. Because this method is not common, there are few appliances designed for it; however, one brand name system is the "Coffee Toddy" which has been reviewed by several newspapers and cooking magazines.[2]

Steeping

• A cafetière (or French press) is a tall, narrow glass cylinder with a plunger that includes a wire mesh filter composed of metal or nylon. The coffee and hot water are combined in the cylinder (normally for four to seven minutes) before the plunger, in the form of a metal foil, is depressed, leaving the coffee at the top ready to be poured. This style of "total immersion brewing" is considered by many coffee experts to be the ideal way to prepare fine coffee at home . Depending on the type of filter, it is important to pay attention to the grind of the coffee beans, though a rather coarse grind is almost always called for.[3].
• Coffee bags (akin to tea bags) are much rarer than their tea equivalents, as they are much bulkier (more coffee is required in a coffee bag than tea in a tea bag). This method of brewing coffee is particularly useful for those on camping trips, when extra weight is an issue.
• Malaysian coffee is often brewed using a "sock", which is really just a muslin bag shaped like a filter into which coffee is loaded then steeped into hot water. This method is especially suitable for use with local-brew coffees in Malaysia, primarily of the varieties Robusta and Liberica which are often much stronger in flavor, allowing the ground coffee in the sock to be reused. This same method is used in Colombia to make tinta, black coffee that is often served with panela, a sugar concentrate in cake form.
• A vacuum brewer consists of two chambers: a pot below, atop which is set a bowl or funnel with its siphon descending nearly to the bottom of the pot. The bottom of the bowl is blocked by a filter of glass, cloth or plastic, and the bowl and pot are joined by a gasket that forms a tight seal. Water is placed in the pot, the coffee grounds are placed in the bowl, and the whole apparatus is set over a burner. As the water heats, it is forced by the increasing vapor pressure up the siphon and into the bowl where it mixes with the grounds. When all the water possible has been forced into the bowl the brewer is removed from the heat. As the water vapor in the pot cools, it contracts, forming a partial vacuum and drawing the coffee down through the filter.

Gallery of common brewing methods

Pressure:

• 
  Home espresso machine.
• 
  Commercial espresso machine.
• 
  Moka pot.

Gravity and steeping:

• 
  Electric drip brewer.
• 
  Cafetière/French press.
• 
  Vacuum brewer.

Presentation

Hot drinks

Cappuccino

Espresso-based, with milk

• Caffè breve is an American variation of a latte: a milk-based espresso drink using steamed half-and-half (light - 10 per cent - cream) instead of milk.
• Caffè latte (or caffè e latte, not to be confused with just latte which is Italian for "milk") is espresso with steamed milk, traditionally topped with froth created from steaming the milk. A latte comprises one-third espresso and nearly two-thirds steamed milk. More frothed milk makes it weaker than a cappuccino. A latte is also commonly served in a tall glass; if the espresso is slowly poured into the frothed milk from the rim of the glass, three layers of different shades will form, with the milk at the bottom, the froth on top and the espresso in between. Often sugar or flavored syrup will be added to a latte. Common flavors are caramel and vanilla, yet other flavors are often added as well.

A café Latte.

• Caffè macchiato — macchiato meaning "marked" or "spotted" — is an espresso with a small amount of steamed milk added to the top, usually 1–2 oz. As with latte, sometimes sugar or flavored syrup will be added to a macchiato. The most commonly used flavors are caramel and vanilla, but others can be added as well.
• Cappuccino comprises equal parts espresso and milk and froth, and is occasionally garnished with spices or powdered cocoa.
• Flat white is one part espresso with two parts steamed milk, but no foam, usually served in a cappuccino cup. This is a specialty of Australia and New Zealand, particularly favored in the latter. The difference between a flat white and a latte is that a flat white is usually served in a smaller cup, has no foam, and is more potent.
• Galão is a Bica (Portuguese espresso) to which is added hot milk, tapped from a canister and sprayed into the glass in which it is served.
• Latte macchiato is the inverse of a caffè macchiato, being a tall glass of steamed milk spotted with a small amount of espresso. As with the latte and the caffe macchiato, sugar or syrup can be added to a latte macchiato. Common flavors are caramel and vanilla, but others are sometimes used.
• Mocha is a latte with chocolate added.

Espresso-based, without milk

• Americano style coffee is made with espresso (normally several shots), topped with hot water to give a similar strength (but different flavor) to drip-brewed coffee; famous in America.
• Bica is a Portuguese espresso, but a little bit softer.
• Long black is similar to Americano, but prepared in different order (espresso is added to water instead of vice versa); famous in Australia.
• Lungo is different from an Americano. It is usually a double shot of espresso run through the machine; all the water runs through the beans, as opposed to adding water.

Brewed or boiled, non espresso-based

• Black coffee is drip-brewed, percolated, vacuum brewed, or French-press-style coffee served without cream. Some add sugar.
• White coffee is black coffee with unheated milk added. Some add sugar. (Note: though having a similar term, this is not to be confused with the Beirut herbal tea or Ipoh town coffee blend).
• Café au lait is similar to latte except that drip-brewed coffee is used instead of espresso, with an equal amount of milk. Some add sugar.
• Kopi tubruk is an Indonesian-style coffee similar in presentation to Turkish coffee. However, kopi tubruk is made from coarse coffee grounds, and is boiled together with a solid lump of sugar. It is popular on the islands of Java and Bali and their surroundings.
• Indian (Madras) filter coffee, particularly common in southern India, is prepared with rough-ground dark roasted coffee beans (e.g., Arabica, PeaBerry). The coffee is drip-brewed for a few hours in a traditional metal coffee filter before being served with milk and sugar. The ratio is usually 1/4 decoction, 3/4 milk.
• Greek coffee is prepared similarly to Turkish coffee. The main difference is that the coffee beans are ground into a finer powder and sugar is added during the process. It does not contain other flavours and usually is not served with milk. The reason why Greek coffee grounds are finer is that during the Turkish occupation of Greece coffee was manufactured in centrifugical mills; the Turks would keep the heaviest grained coffee, while Greeks used to take whatever was rejected from the centrifugical process. Greek coffee is served in a small cup with a handle, and accompanied always by a small cookie and a glass of water.
• Vietnamese-style coffee is another form of drip brew. In this form, hot water is allowed to drip though a metal mesh into a cup, and the resulting strong brew is poured into a glass containing sweetened condensed milk which may contain ice. Due to the high volume of coffee grounds required to make strong coffee in this fashion, the brewing process is quite slow. It is also highly popular in Cambodia and Laos.

Fortified coffee

• Red Eye is one espresso shot added to a cup of coffee (typically 7-16oz). Some add milk or sugar.
• Black Eye is two espresso shots added to a cup of coffee (typically 7-16oz). Some add milk or sugar.

Flavored coffees

• Flavored coffee: In some cultures, flavored coffees are common. Chocolate is a common additive that is either sprinkled on top or mixed with the coffee to imitate the taste of Mocha. Other flavorings include spices such as cinnamon, nutmeg, cardamom, or Italian syrups. In the Maghreb, the orange blossom is used as a flavoring. Vanilla- and hazelnut-flavored coffees are common in the United States; these are usually artificially flavored.

Madras filter coffee

• Turkish coffee is served in very small cups about the size of those used for espresso. Traditional Turkish coffee cups have no handles, but modern ones often do. The crema or "face" is considered crucial, and since it requires some skill to achieve its presence is taken as evidence of a well-made brew. (See above for preparation method.) It is usually made sweet, with sugar added after the brew process begins, and often is flavored with cardamom or other spices. In many places it is customary to serve it with a tall glass of water on the side.
• Chicory is sometimes combined with coffee as a flavoring agent, as in the style of coffee served at the famous Café du Monde in New Orleans. Chicory has historically been used as a coffee substitute when real coffee was scarce, as in wartime. Chicory is popular as an additive in Belgium and is an ingredient in Madras filter coffee.

Cold drinks

• Iced coffee is a cold version of hot coffee, typically drip or espresso diluted with ice water. Iced coffee can also be an iced or chilled form of any drink in this list.
• Frappé is a cold coffee drink made from instant coffee. It was created in Greece in 1957 in the city of Thessaloniki. This type of coffee is probably consumed in Greece more than traditional Turkish coffee, especially in the spring and summer months. Frappé is served cold, with a drinking straw, either with or without sugar or milk.
• Ice-blended coffee (trade names: Frappuccino, Ice Storm) is a variation of iced coffee. The term Frappucino was coined by Starbucks (a portmanteau of Frappé and Cappuccino: Frappuccino). Other coffeehouses serve similar concoctions, but under different names, since "Frappuccino" is a Starbucks trademark. One commonly used by many stores is Ice Storm. Another prominent example is the Javakula at Seattle's Best Coffee. A frappuccino is an iced latte, mocha, or macchiato mixed with crushed ice and flavorings (such as vanilla/hazelnut if requested by the customer) and blended.
• Thai iced coffee is a popular drink commonly offered at Thai restaurants in the United States. It consists of coffee, ice, and sweetened condensed milk.
• Igloo Espresso a regular espresso shot poured over a small amount of crushed ice, served in an espresso cup. Sometimes it is requested to be sweetened as the pouring over the ice causes the shot to become bitter. Originating in Italy and has migrated to Australian coffee shops.
• Cold brewed coffee Toddy coffee is a filtered, drip-style process of brewing coffee slowly (12 hours) with cold water to produce a strong coffee concentrate, often served diluted with water or milk of choice.

Confectionery (Non-drinks)

• Chocolate-covered roasted coffee beans are available as a confection; eating them delivers more caffeine to the body than does drinking the same mass (or volume) of brewed coffee (ratios depend upon the brewing method) and has similar physiological effects, unless the beans have been decaffeinated.

Artificial Coffee Flavour Products

• Both Pepsi and The Coca Cola Company have coffee-flavoured soft drinks on the market.

External links

• The Coffee FAQ: Brewing Techniques