Green Coffee Beans
In general, coffee is grown in an area ranging from 25 North of the equator to 25 South in a belt that runs around the world. The only coffee grown commercially in the United States comes from Hawaii and is called "KONA" coffee. There are two principal species of commercial coffee; Aribica, and Robusta. The two primary commercially grown species of coffee are Arabica and Robusta. Robusta thrives in low lying, moist river deltas which are much easier to farm than the highlands required for Arabica coffees. Robusta flowers up to four times per year, producing about four pounds of coffee per plant. High yield combined with low farming cost make Robusta a favorite with large commercial coffee companies which are more concerned about cost than taste. While Robusta beans are less expensive than Arabica, they tend to be harshly acidic and woody in flavor. Under natural conditions, coffee trees grow to about 15 to 30 feet at maturity but normally they are pruned to a smaller height to permit easier picking. Growing conditions such as soil, temperature, altitude and rainfall vary considerably. Each of these has an important effect on beverage quality.
There are about 50 varieties of coffee in ordinary commercial use. These varieties fall into three general classifications. "Brazils" are coffees grown in the country of Brazil. "Milds" include all other varieties except "Robustas" which have recently been separated from "Milds". The terms "Milds", "Brazils" and "Robustas" do not describe their flavor or quality. There is much misuse among salesmen and customers of the word "Milds". Salesmen occasionally tell prospects that their blend of coffee is all "Milds". While this may be correct, it does not have any practical bearing on quality. Furthermore, there are customers who are under the impression that a "Mild" coffee is one that is mild in flavor and lacks bitterness. This is a misconception.
Brazilian coffees are named after a region in which they are grown or the port through which they are shipped. Common names for Brazilian coffees are Santos, Par anas, Bahias, Pernambucous, and many others. Mild coffees are named after the country in which they are grown. They include Colombians, Mexicans, Salvadors, Guatemalas, etc. These growths may in turn be broken down further. As an example, Colombians may be called Medellins, Manizales, or by other names representing the district or area of Colombia in which they grow. Robusta coffees come for the most part from Africa and are named for the country of origin such as Congos or Ivory Coasts, or the district of growth such as Ambriz or Encoge.
A coffee tree is grown from seed is transplanted three times before reaching its maturity. from the time of the original planting to the first picking about five years elapse. In some countries harvest is only available once a year. In other countries trees are harvested twice yearly. The yield from a tree varies but on average, one tree will produce one pound of coffee annually during its productive years. About 3,500 hand picked beans are required to make one pound of roasted coffee. Commercial blends are are made up of numerous varieties of coffee. In addition the blend may be changed from year to year or from one month to another depending on the quality of of the growths available. It is work of the expert blender to maintain a uniform blend flavor at all times even though the varieties composing the blend may undergo constant change.
When coffee fruit matures on a tree it closely resembles a cherry. These cherries are hand picked as they ripen and then are processed for shipment. Each cherry contains two flat-faced beans facing each other. The beans are protected by three external layers of skin. Removal of these external layers is accomplished in the producing country by either one of two methods. Green coffee can be processed by the wet or dry method. If the wet method is used the coffee is called "washed" and is generally regarded as more desirable. The harvested cherries are dumped into fresh water tanks where they are soaked. Undesirable berries float to the surface and are skimmed off. The ripe ones are transported to a de pulping machine by a stream of water. De pulping removes the outer layers of the coffee cherry and leaves the seeds covered with parchment and a sticky mucilage-like substance. From there they will flow on to large fermenting tanks where they are allowed to soak about one day to soften the mucilage. After fermentation the beans are again washed in fresh, clear water and then spread in the sun to dry for several days. Next, the beans are put through a hulling machine to remove the parchment and silver skins after which they are ready for hand sorting to remove imperfections.
In the dry method, ripe and green berries are stripped from the trees and dumped into sluiceways which carry them to drying grounds. Here they are spread out to dry for 2 to 3 weeks. They are then hulled and graded. Beans prepared by this method are called "naturals" or "unwashed". Later the beans run through sieving machines which sort them into different sizes. The coffee is packed in heavy jute or fiber bags for shipment to market. the filled weight of these bags varies in different locations, but 60 kilograms or 132 lbs. is used as a standard basis.
Green coffee purchasing is done through three channels:
- "Spot" is coffee actually landed in port and stored in a warehouse.
- "Shipment" is actual coffee which will be shipped at a specific time.
- "Futures" are contracts bought and sold through the New York Coffee and Sugar Exchange. Actual coffee is rarely delivered against these contracts. "Futures" are mainly used for hedging to protect price position.
When the green coffee is sold in this country it goes through one of its most interesting phases. First, the beans are graded according to the number of imperfections, from No. 2 down to No. 8. In theory, No. 1 would be coffee completely free from imperfections. This is so rare that it is not used.
The rating scale for a 300 gram sample is:
- No. 2 - 6 black beans
- No. 3 - 13 black beans
- No. 4 - 29 black beans
- No. 5 - 60 black beans
- No. 6 - 115 black beans
- No. 7 and No. 8 are much greater than 115 black beans and are graded by comparison with standard types.
Other imperfections, such as shells, stones, sticks, etc., are evaluated by a scale comparing them to black beans.
- 3 shells equal 1 black bean
- 5 broken beans equal 1 black bean
- 2 small stones equal 1 black bean
After grading, expert "cuppers" check the product to determine its flavor quality. they start by roasting a small batch of beans in a gas or electric sample roaster. The coffee is then ground and usually eight grams placed in a cup. Boiling water is poured over this sample and the "cupper" begins his tests by smelling the aroma. The coffee is then tasted. In this process a spoonful of coffee is sucked into the mouth and spread over the taste buds - front and back. The taster savors this quality and then spits it into a large brass cupsidor. Expert cup tasters never swallow coffee when tasting. At this point a whole new dictionary of words enters the picture. The flavors detected are referred to by the coffee taster's own set of words. A few of the most common have been appended to the glossary see our TERMS & PHRASES for those words. From his many years of experience the coffee taster appraises the green coffee and from this proceeds to build up a blend which will meet the established standards of his particular company.