The Coffee Bean

Everything You Want To Know About the Coffee Bean

Fresh-roasted gourmet coffee beans are a true delight! Arabica coffee beans grown at high elevations in the world’s prime green coffee growing regions, cultivated with care in fertile, well-drained soils and then hand-picked at peak ripeness, processed with care, and roasted properly for the particular bean.

These fresh-roasted gourmet coffee beans then need to be ground properly just before brewing (a Conical Burr Grinder is preferable), and then brewed properly with the right water, water temperature, and brewing methods. Then you will have the perfect cup of coffee or perfect Espresso shot, depending on what is your preference.

Jump over to The Top 10 Best Coffees in the World.

It All Starts With the Coffee Bean

The coffee bean is the seed of the coffee plant. It is found at the center of the coffee plant fruit, which is known as the coffee cherry. Most coffee cherry have two half-seeds, or half-beans, though typically from one to seven percent of a coffee crop will have one whole bean, and these are known as peaberry coffee beans.

The immediate layer around the coffee bean within the cherry is known technically as the spermoderm but more commonly called the silverskin. This vestigial remainder of the development of the coffee fruit is in turn covered by what is technically known as the endocarp but more commonly called the parchment skin.

Around this layer of the coffee bean is the slimy parenchyma and then a small layer called the mesocarp and more commonly known as the pulp.

Around all of these layers of the coffee bean is the exocarp, which is the outer skin of the coffee cherry. All of these layers are removed before roasting with the exception of the silverskin which may or may not be left on the beans during the roasting process.

The leftover coffee cherry is typically discarded, though about 10% of the time it is used as fertilizer. Recently, it has been processed and turned into it’s own products – a tea known as Cascara, or ground into a coffee flour.

The Primary Varieties of Commercial Coffees – Arabica and Robusta

The two main coffee plant varietal s are Arabica and Robusta. The Arabica plant has the scientific name Coffea arabica while the Robusta’s scientific name is Coffea canephora var. Robusta. Of lesser importance though commercially grown to some extent is Liberica (Coffea Liberica).

There is a genetic distinction between the Arabica varietal – which has four sets of chromosomes – and the Robusta and Liberica varietals, which each have two sets of chromosomes.

Coffee Plants and Coffee Growing Regions

Arabica coffee beans come in many varietals of coffee plants in different growing regions with some general characteristics holding generally true. For example, coffee beans from Indonesia and India are known for their earthy quality while the Ethiopian Harrar coffee bean is known for its notes of blueberry. Central American coffees are known for offering citrus tones.

Robusta coffee beans are used primarily for instant coffee but also added  as small percentages of coffee bean blends for espresso to impart a particular desired flavor and for their ability to improve the espresso shot crema.

Excessive cold or heat are damaging to Arabica plants which are generally much more sensitive to temperature than Robusta coffee plants. While gourmet Kona coffee beans are grown at elevations between 1,500 and 3,000 feet while many other prime Arabica coffee bean growing regions cultivate the plants at much higher elevations, as high as 9,000 feet above sea level.

Profiles of Coffee by Country of Origin – Characteristics of the Coffee Bean

Generalizing about a particular country’s coffee is only useful to a degree as many country’s have vastly different growing regions within the country, producing widely varying qualities of coffee.

These coffees may also be grown from starkly different coffee plant varietals and the genetics of the coffee plant have a significant effect on the characteristics of the coffee beans being grown. This includes the overall flavor qualities of the coffee bean including the aroma, acidity, body (mouthfeel), sweetness, bitterness and aftertaste, also known as the finish.

Fine Arabica coffee plants require not only a cool climate that never experiences frost, they also require fertile, well-drained soil. Many fine Arabica coffees are grown in the partial shade of a forest canopy or in the shade of other plants.

Robusta coffee plants are generally more resistant to coffee diseases and pests than Arabica coffee plants. These pests include various fungus diseases and the dreaded coffee leaf rust.

Varying Qualities of Arabica Coffee

Many countries, including Brazil, grow large amounts of Arabica coffee plants in less than ideal conditions and elevations, and these coffee beans are often machine picked and are generally known as “Brazils” even when not grown in Brazil.

These “Brazils” are typically machine picked while premium gourmet coffee beans are hand-picked.

Arabica coffee plants generally produce less coffee overall than Robusta plants. Arabica plants are also more difficult to grow than Robusta plants, which grow well at lower elevations. Thus Arabica coffee beans are generally much more expensive than Robusta beans.

About 65% of all of the green coffee beans grown worldwide are Arabica coffee beans. The quality of these Arabica coffees varies considerably, from harsh quality Arabicas grown with little care at low elevations and machine picked, to high quality Arabicas grown at high elevations and hand picked.

Some coffee bean connoisseurs will tell you that a finely grown and processed Robusta coffee bean varietal is far superior to a very poorly grown and processed Arabica coffee bean varietal.

Different Types of Coffee Processing of the Coffee Bean

The two main types of coffee bean processing are known as wet processing and dry processing, and they differ in how they deal with the pulp of the coffee cherry after harvest.

Wet processing generally involves allowing the coffee cherry with the exposed fruit (often with the outer skin removed) are placed in tanks to ferment which allows the bacteria and enzymes to remove the coffee pulp from around the coffee beans.

Following the fermentation stage the coffee beans are rinsed and then dried, followed by milling which removes the remaining layers around the coffee beans.

Dry processing involves typically first rinsing the coffee cherry and the laying them out to dry, usually in the sun or else using drying machines. The pulp of the coffee cherry is allowed to dry around the bean and the fermentation at this stage imparts particular taste characteristics to the coffee beans.

Once the coffee beans have dried, then machine processing may be used to removed the outer layers around the coffee beans.

Another fairly common coffee bean processing method is known as semi-washed processing and involves first removing the outer skin of the coffee cherry and then allowing the pulp to dry around the coffee beans. During hulling the pulp may be moistened.

Wet processed coffees beans are generally known for their fine acidity and overall clarity and clean quality, while dry processing is said to improve the coffee’s body (mouthfeel) and provide a notable complexity to the coffee beans. The semi-washed coffee beans are an attempt to gain the positive benefits of both the wet and dry processing methods.

Coffee Bean Characteristics by Coffee Plant Varietals

There are many traditional coffee plant varietals as well as many that have been more recently developed through selective breeding of plants and extensive coffee plant research.

Much of the goal of research has been to develop varietals of coffee plants with gourmet coffee bean characteristics, yet which are also resistant to coffee diseases and pests, and which are hardy plants able to grow well in varying climate and soil conditions.

Two well-known Arabica coffee plant varietals are Typica and Bourbon, both of which were naturally occurring Arabica varietals.

Many other Arabica coffee bean varietals were derived from these two prominent Arabica varietals and produce highly respected coffee bean qualities. Some other well-known coffee plant varietals include Blue Mountain, Catimor, Mundo Novo, Pacas, Caturra and Maragogype.

Aged and Monsooned Coffee Beans

Coffee beans may also be aged or monsooned which creates differing taste characteristics including deepening the flavors and muting the acidity.

Monsooned coffee beans are exposed to the moist winds and rains of the monsoon season and this may be done for as long as three years. Aging or monsooning may enhance high coffee bean quality yet there is no guarantee that the beans will be considered premium gourmet coffee.

How Are Coffee Beans Decaffeinated?

The coffee bean decaffeination occurs primarily by one of three methods including the Water Process, Carbon Dioxide Process and solvent process.

The Solvent process, also known as the European process, of decaffeination of coffee beans and involves using either ethyl acetate or methylene chloride as a solvent. A solvent may be used either directly or indirectly.

In the direct method the coffee beans are first steamed which forces them to expand and thus become more permeable. Then the solvent is applied which extracts the caffeine from the coffee beans.

When this is completed then the solvent is treated in order to extract the caffeine so that the solvent can be used again. Steaming also removes any residual solvent from the coffee beans.

The Indirect process of decaffeination involves first soaking the coffee beans in hot water to remove any soluble compounds including any caffeine in the beans. Then the water is drained away and mixed with the solvent which in turn bonds with the water.

At this point the caffeine-solvent mixture has less density than the water so it floats to the top and is removed. After this the coffee beans and water can be mixed so that the coffee bean taste is restored.

In the Water Process of Decaffeination of coffee beans, activated charcoal is used instead of solvent to remove any caffeine from the water. Also the first batch of coffee beans used is thrown out and the removed water is combined with a new and untreated batch of coffee beans. This means that only the caffeine within the new beans will dissolve and can be removed.

In the Carbon Dioxide Process, or Sparkling Water Process of Decaffeination, supercritical gas fluids are used by compressing gasses above critical pressures and temperatures. This material is combined with the coffee beans and combines with the caffeine in the beans. It is then isolated so that the caffeine can be removed using either activated charcoal (in the Carbon Dioxide Method) or water (in the Sparkling Water method).

Thank You for Visiting Espresso Coffee Guide and Reading About the Coffee Bean!


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