COFFEE

The coffee plant is an evergreen tree/bush, which is grown commercially in tropical climates throughout the world. It requires not only a hot climate, but also high rainfall, a rich soil and a high altitude. The coffee plant is unable to survive any wide variations in temperature or frost conditions. The part of the plant that is used in coffee production and processing is the coffee berry. Commercially, there are three varieties of berries that are grown:
1. Coffee Arabica
Supplies the largest and the best quality of coffee. It has a bold regular sized bean and a fine flavour. It is very prone to disease and requires careful cultivation. It grows in Brazil, Colombia, Kenya, Jamaica and India.
2. Coffee Robusta
Produces the second most popular coffee. The beans are generally smaller and of lower quality. It is a more hardy plant, has higher yield, is disease resistant and is grown in East and West Africa.
3. Coffee Liberica
Produces the third main type of coffee. It is a hardy and robust plant and sometimes grows wild. The beans are large in size, but of an inferior quality.
The main exporting countries of the coffee beans are Brazil, Uganda, Columbia, Kenya, the Ivory Coast and the Congo.

Classification of Coffee
Coffee may be classified under the following headings:
1. By their country of origin (Kenya, Brazil).
2. By their type (Robusta, Arabica, Liberica).
3. By the grade of the beans (Inferior or Superior).
4. By the method of processing (Wet or Dry).
5. By the blend (Coffee mixtures with chicory or figs).
6. By the catering use (For espresso machines, vending machines, for bakery and confectionary).

Processing of Coffee
When the berries are ripe, they are picked by hand and taken or exported to the processing plant. The berries are about the size of a small cherry and consist of an external red skin, a layer of pulp, a tough parchment like inner membrane, a thin silver skin and finally two beans – rounded on one side and flat on the other – with the flat sides pressed against each other. Depending on the country where the processing takes place, either one of the following methods will be used:
1. The Dry Method
It is used in the country which don’t have abundant water supply or where the value of cured beans doesn’t warrant the extra costs of washing. The berries are spread out thinly in the sun and left till the pulp shrivels tightly onto the parchment and allowed to dry. The berries are then put through a hulling machine, which removes the parchment and the pulp in one stage. Very little sorting of the berries is done and some may carry traces of the silver skin and lack the appearance of the washed beans.
2. The Wet Method
This method is used in countries which have a sufficient water supply and where the quality of the bean grown warrants extra processing costs. The berries are put through a de-pulping machine to remove the fleshy part of the berry leaving the two seeds in their jackets. They are then placed in large vats and are allowed to ferment partially for 24-40 hours. This fermentation serves two purposes. It helps to develop the aroma of the cooked coffee and also helps to remove any adhering pulp. When the fermentation stage is complete, the beans are thoroughly washed and then spread out in the sun to dry completely. The next stage is the removal of the parchment by machines, to leave just the clean olive green beans.

Grading
The coffee grades vary with the country of origin, with letters or sometimes with the numbers used. It is usually accepted that the largest normal shaped beans are best quality and possess a fuller flavour, aroma and body than the other beans.

Coffee Roasting
The green coffee bean has little or no flavour. The flavour, aroma and colour of liquid coffee are developed by roasting the coffee beans, which causes the cell walls to be ruptures, making the flavouring and the aromatic qualities of the natural oil content readily available to extraction by hot water. Roasting can vary from light to dark. A dark roast gives a slightly bitter characteristic and is widely used for espresso and after-dinner coffee. A light roast gives a mild taste, suitable for general purposes. Roasted coffee beans are cooked and are liable to deterioration. Any beans not used immediately after roasting, must be stored in an air-tight container.

Coffee Grinding
The roasted coffee bean is next ground to enable the flavour, aroma and colour to be easily extracted. The degree to which the coffee beans are ground is related to the type of coffee making-equipment that is being used. Finer the grains are, stronger/bitter is the flavour. Prolonged infusion doesn’t add anything of advantage except possibly bitterness.
Ground coffee deteriorates even faster than the roasted beans. This is because the flavouring oils are highly volatile. Ground coffee will lose 20% of its freshness in one day and upto 50% in three weeks, if not stored in an air-tight container. Moreover, it will develop certain staleness as a result of volatile oils being easily oxidized.

Coffee Blending
Many coffee blends are available from coffee merchants (breakfast, mid-morning or after-dinner use). The blending is carefully done by experts in a manner similar to tea tasting and blending, to produce a standard product of high quality, flavour, aroma and colour, and available throughout the year at a standard price.

Coffee Mixtures
Some well known blends of coffee are a blend of coffee with either chicory or figs. French coffee is a blend of coffee and chicory. Viennese coffee is a blend of dried and roasted figs and coffee. Chicory helps to lower the costs and help to produce a smoother and sweeter liquid.

Instant Coffee
This is the convenient form of coffee most widely used today. No special equipment is required and the product is of an acceptable standard. Instant coffee is pure coffee concentrate, which is atomized to a fine mist in a drying chamber containing hot air. Accelerated freeze dry method has produced an instant coffee that resembles the freshly ground coffee and which dissolves completely quickly.

Caffeine Free Coffee
Caffeine is an alkaloid substance, which produces the stimulating effect in a cup of coffee. It is also responsible for the bitterness of coffee. 87% of the caffeine can be removed by processing the green beans under steam in a vacuum. It is ideal for persons with heart ailments and those who have been advised not to drink regular coffee. Decaffeinated coffee, by law, must not contain more than 0.1% of caffeine.

Coffee Concentrates
These are concentrated extracts of coffee, mainly used as a flavouring agent in commercial bakery and confectionary production.

Coffee Bags
These are similar to tea-bags and contain freshly ground coffee and some instant coffee.

Catering Packs
These are similar to catering packs for tea and will produce a specific quantity of coffee. The variety of blends, degree of roasting and grinding gives the caterer a very wide choice.

Storage
Care must be taken with regards to the storage of coffee. Since the flavouring oils are volatile, some flavour is lost after roasting and then again after grinding. Coffee powder should ideally be vacuum- packed and then stored in sealed airtight containers.

Preparation of Coffee Beverage
Good coffee can be made by several methods. The chief factor is the control of the method in order to avoid the loss of flavour and the extraction of indigestible amount of bitter substance.

Filtration
The drip pot consists of an upper compartment, which is perforated and lower compartment, which is a receiver for the filtered beverage. The perforations of the upper compartment are covered with thin filter paper or with cheesecloth to prevent the passage of coffee into the beverage. By this method, the water filters through the coffee into the lower compartment.
Another type of pot commonly used for filtration is the Vacuum Coffee Maker. The upper compartment, which holds the coffee, has an open tube that extends to the bottom of the lower compartment by the help of a cloth covered disc, held over the tube opening. Water is heated in the lower compartment for a particular period of time, until most of the water rises into the upper compartment. The pot is kept aside until all the water filters through the coffee and passes back into the lower compartment. Coffee beverage is heated and served.

Percolation
The percolator includes a pot, a coffee basket and a hollow stem to support the basket. Measured coffee is placed in the basket, which is placed on the steam, and then both are inserted into the pot. When heat is applied, the water is forced up by steam and spreads over the coffee basket onto the coffee, and down into the pot. Only a small portion of the water at any one time reaches the basket. When percolation begins, the heat is adjusted so that water reaches the top of the basket about every two seconds. This gentle percolation is continued for six to eight minutes, until the desired strength is achieved.

Boiling or Steeping
Although coffee made by this method is usually described as boiled, the beverage made by heating the coffee and water together is more desirable in flavour, if not actually allowed to boil. Steeping (extracting flavour below boiling point) extracts much less of the bitter substances from coffee than boiling. The length of time of steeping varies with the temperature of water mixed with the coffee.

Steps in Coffee Making
Coffee is made by extracting flavours from ground coffee by dissolving it in hot water. The essence of making good coffee is to extract enough of these solids to make flavourful beverage, but not to brew so long as to make the coffee bitter. Points to be observed are as listed:
 Use fresh coffee.
 Use the right grind and the right brewing grind. A coarse grind requires more time for extraction than a fine grind.
Grind Extraction Time
Fine or Vacuum 2-4 minutes
Drip or Urn 4-6 minutes
Percolator 6-8 minutes
 Use the right proportions.
 Use fresh water.
 Use water at the right brewing temperature [90°C to 93°C (195°F to 200°F)].
 Use a good brewing procedure.
 Use clean equipment.
 Use good filters.
 Use proper holding procedures.
 Don’t hold coffee for more than an hour.

Different types of Coffee served
Cona Coffee/Vacuum Infusion
This method of making coffee has considerable visual appeal and has the advantage that the coffee is served always fresh as only limited quantities are made at one time. The method of making coffee is similar to the percolator method. The lower bowl is filled with cold water or freshly heated water. The filter is placed in the upper bowl and the required quantity of coffee is added to the amount of water being used. The upper bowl is then set in the lower bowl, making sure it is securely in place, and the ware is heated. As the water reaches its boiling point, it rises up into the upper bowl, mixing with the ground coffee. It may be carefully stirred at this stage. On reducing the heat, the coffee, liquid passes back into the lower bowl, leaving the coffee grounds in the upper bowl. The coffee in the lower bowl is ready for use and should be served at 82°C, with hot or cold milk or cream and sugar.

Espresso Coffee
This method, Italian in origin, involves passing steam through the finely ground coffee and infusing under pressure. Each cup of coffee is made freshly for the customer and served black in small cups.

Cappuccino Coffee
Cappuccino coffee is prepared by the addition of milk heated by a high pressure steam injector. It comprises of equal parts of espresso and hot milk topped with cinnamon and nutmeg and usually whipped cream.

Turkish Coffee
It is made from darkly roasted and ground Mocha beans. Water is boiled in special copper pots and sugar is added at this stage, as this coffee is never stirred once poured out. Finely ground coffee may be added or boiled water poured onto the grounds. Once the coffee has been stirred in, the copper pot is taken off the direct heat and the cooling causes the grounds to settle. It is brought to boil and allowed to settle twice more and is then sprinkled with cold water to settle any remaining grains. The coffee is served in small cups. Vanilla pods may be added to flavour the coffee.
Iced Coffee
It is a strong black coffee served with an equal quantity of cold milk or cream. It is served in a tall glass, with ice cubes.

Irish Coffee
Strong black coffee is poured into a Paris goblet with sugar in it. One measure of Irish whiskey mixed in and double cream is poured slowly over the back of a spoon onto the surface of the coffee. The coffee must not be stirred – the best flavour is obtained by drinking the whiskey flavoured coffee through the cream. If brandy is used instead of whiskey, the coffee is known as Café Royala.