Everyone knows coffee when they see it. Dark roasted or light roasted beans with a warm aroma that perks up your nose. But those roasted coffee beans don’t start out that way. They start out, as cherries.
Coffee cherries grow on trees that can reach 30 feet high or bushes that can be as small as 2-3 feet. The most common trees have dark waxy leaves that contrast against their beautifully cherry fruit which grow on the trees limbs. But they can also be found with purple or yellow leaves, to the predominant dark green.
It’s common to see coffee flowers blooming on a tree with green and ripe fruit at the same time.
On average a coffee tree can live 20 to 30 years as long as the climate doesn’t experience vast fluctuations in temperature. They primary love rich soil, mild climates, frequent rain and moderate shady areas.
History Of Coffee
The history of coffee goes at least as far back as the thirteenth century with a number of myths surrounding its first use. The original native population of coffee could have come from Ethiopia or Kenya, and it was cultivated by Arabs from the 14th century.
The earliest credible evidence of either coffee drinking or knowledge of the coffee tree appears in the middle of the fifteenth century, in the Sufi monasteries of Yemen. By the 16th century, it had reached the rest of the Middle East, Persia, Turkey and northern Africa. Coffee then spread to Balkans, Italy and to the rest of Europe, to Indonesia and then to the Americas. ~ Wikipedea – History of Coffee .
Today coffee is grown around the world. Brazil is by far the largest supplier of coffee today. Their fairly flat fields are prime locations for large scale production and they host the largest number of coffee companies. Because of their terrain, the process to grow, harvest and produce coffee is very modernized. Giving them an advantage over other countries.
Columbia also has a big part in the coffee making industry. They produce about 2/3rds of the crop as Brazil. Here their growing to production is more labor intensive because of the mountainous terrain.
Other countries that fall along the equator also produce coffee products as these regions hold the prime elements for optimal growing. Here in the states, Hawaii is the only location that produces coffee that we’ve come to know as Kona. One of our favorite varieties.
Coffee trees come from a class of plants known as Coffea. Within this class of plants there are over 6,000 species of tropical trees and shrubs and of those over 100 are considered to be Coffee trees or shrubs. In the commercial coffee industry, there are two important coffee species — arabica and canephora, more commonly called robusta.
A Description From the National Coffee Association USA:
Varieties: Bourbon, Typica, Caturra, Mundo Novo, Tico, San Ramon, Jamaican Blue Mountain
Coffea arabica is descended from the original coffee trees discovered in Ethiopia. These trees produce a fine, mild, aromatic coffee and represent approximately 70 percent of the world’s coffee production. On the world market, arabica coffees bring the highest prices. The better arabicas are high grown coffees — generally grown between 2,000 to 6,000 feet above sea level — though optimal altitude varies with proximity to the equator. The important factor is that temperatures must remain mild, neither too hot nor too cold, ideally between 59 – 75 degrees, with about 60 inches of rainfall a year. The trees are hearty but a heavy frost will kill them. Arabica trees are costly to cultivate because the terrain tends to be steep and access difficult. Also, because the trees are more disease prone than robusta, they require additional care and attention. Arabica trees are self pollinating. The beans are flatter and more elongated than robusta and lower in caffeine.
Most of the world’s robusta is grown in Central and Western Africa, parts of Southeast Asia, including Indonesia and Vietnam, and in Brazil. Production of robusta is increasing, though it accounts for only about 30 percent of the world market. Genetically, robusta carries fewer chromosomes than arabica and the bean itself tends to be slightly rounder and smaller than an arabica bean. The robusta tree is heartier, more disease and parasite resistant, which makes it easier and cheaper to cultivate. It also has the advantage of being able to withstand warmer climates, preferring constant temperatures between 75 and 85 degrees, which enables it to grow at far lower altitudes than arabica. It requires about 60 inches of rainfall a year and cannot withstand a frost. Compared with arabica, robusta beans produce a coffee which has a distinctive taste and about 50-60% more caffeine. Robusta is primarily used in blends and for instant coffees.
The Coffee Cherry
The structure of the coffee cherry has 7 parts.
1: center cut
2: bean (endosperm)
3: silver skin (testa, epidermis),
4: parchment (hull, endocarp)
5: pectin layer
6: pulp (mesocarp)
7: outer skin (pericarp, exocarp)
The center bean is what we use to make coffee. But before it can be brewed into our favorite morning beverage, it has to be roasted.
Coffees grown in higher elevations require much less pesticides as there is a much lower risk of pests. Those grown at lower levels are more susceptible to bugs and will require a higher use of pesticides. The roasting process not only enriches flavor in the bean, but it’s also an essential process for removing any pesticides that were used in the growing process.
Processing The Cherries
Once the beans are harvested, any twigs, leaves or other plant material are removed. Next they go through one of two processes.
The Dry Method
The age old practice of laying out the bean on a mat in the sun is still used in some areas today. Especially on the continent of Africa. The beans are turned or raked several times during the day to prevent the cherries from spoiling. They are covered at night to protect them from moisture, or rain. This process can take several weeks to sun roast the cherries until they have only about 11% moisture left in the fruit. Then they are moved and stored in warehouses to await shipment and further processing.
The Wet Method
The modern wet method is quicker and requires a number of additional steps to process the cherries. The pulp is removed from the coffee cherry after harvesting and the bean is dried with only the parchment skin left on. The cherries then go through a pulping machine where the skin and pulp is separated from the bean. Now that the bean is left, they are weighed and separated through water channels, the lighter beans floating to the top, while the heavier, ripe beans sink to the bottom.
The beans are then transferred into large rotating drums where they are once again separated, this time by size. In their new groupings, they are placed in large fermentation tanks to remove the slick layer of mucilage (also called the parenchyma). They will remain in these tanks from 12 to 48 hours where a natural breakdown of material occurs leaving the bean and some if not most of its outer parchment shell. From here, the go through additional water baths for additional cleaning and then they head off for drying.
In both processes the beans are dried to 11% moisture levels, either by the sun or in warm tumblers. At this stage they are called parchment beans, meaning there is still some parchment left of the bean. Like the dry method beans, they are transferred to storage areas and await shipment.
Before the beans are exported they are hulled, sometimes they are polished (an optional process in which any silver skin that remains on the beans after hulling is removed in a polishing machine) and then they are sorted by size and weight, and graded by color and imperfections.
These milled beans now become “green coffee” beans. Approximately seven million tons of green coffee is produced worldwide each year. They are transported in plastic containers to keep them dry and to ensure they don’t spoil.
Roasting The Beans
Roasting the coffee bean is how we bring out the flavor of the bean. Heating up the bean to varying levels pulls out the natural oil in the bean known as caffeol. Heat it too much and you burn off too much caffeol. Don’t heat it up enough and you don’t bring out enough flavor.
In commercial quantities, green coffee goes through a roasting process that is carefully controlled by computers and roasting machines. But in smaller quantities, the do it yourself roaster must rely on their own judgement. The higher the roast, the more uniform the resulting flavor.
Green coffee beans are heated to between 356ºF – 464ºF (180ºC and 240ºC) for 8 to 15 minutes, depending on the degree of roast required. The hotter the bean is heated, the darker the roast you create. Just like popcorn, when you heat the bean it pops open as moisture explodes inside the bean. Starches are converted to sugar, proteins are broken down and the entire cellular structure of the bean is changed. This is called pyrolysis.
Roasting creates a variety of flavors within the coffee bean.
~ Wikipedia – Coffee Roasting
Unlike tea which relies on oxygenation, coffee beans can be easily damaged by moisture, light and oxygen once they’re roasted. So keeping the roasted bean dry, cool and in a dark place is essential to maintaining its flavor and freshness. This helps to ensure the natural oil in the bean doesn’t evaporate before it can be shipped, ground and placed in your coffee maker at home.
A lot of hard work has gone into one of our favorite beverages. Try not to take it for granted. It has traveled along way and been through much to end up in your cup.