Coffea, the coffee plant, is a flowering tree that produces small red or purple fruit called cherries.
What Is Coffee Considered?
Coffee cherries are drupes (stone fruit), but unlike more familiar drupes such as peaches and apricots, they are grown for their seeds (coffee beans) rather than for their flesh.
Each cherry usually contains two coffee beans. According to the National Coffee Association, a single coffee tree produces about 10 pounds of coffee cherries a year, which equals about 2 pounds of green coffee beans.
Coffee beans weigh less after roasting, so it’s safe to say that an entire coffee tree produces less than two pounds of roasted coffee per year!
Coffee grows on trees that grow to 9 meters (30 feet). But are typically cultivated around 3 meters (9 feet) for ease of picking.
The beans are the seeds of the coffee “cherry” and usually contain two beans in.
The bean is covered with several layers that need to be removed before roasting.
There are two major types of a plant used for coffee, Arabica and Robusta (canephora).
What is Coffee Arabica?
Arabica, has four chromosomes, and Robusta has two; the taste can differ between varieties and regions. Even the same variety but grown in a different region can taste different.
There is a wide range of tastes, such as berry flavor (Ethiopian Harrar). Earthy (Indian and Indonesian coffees), citrus (Central American), and even ‘chocolate’ like you get with Mocha.
Arabica is pretty versatile and can be grown in places like the Kona region in Hawaii. Which can be as low as 300 meters (1000 feet) to regions in Mexico that are over 1200 meters (4000 feet).
Coffee has been known to grow in altitudes as high as 2900 meters (9500 feet) in Ecuador. Although the average elevation would be around 1800 meters (6000 feet).
An effort must be made not to subject the plants to frost or high heat. As it can damage the fruit, too much or too little rain.
Moist well-drained soil is the ideal environment; the coffee plant also does well in well-lit forest regions that offer shade.
Care has to be taken to limit fungus; insects and other pests as Arabica are not very resistant to these threats.
What is Coffee Robusta?
Robusta usually has a harsher taste. Premium Robusta is used in Espressos as it adds an extra bite to the shot and improves the creme.
The drawback of needing a more exact growing environment, is that farmers and processors are unwilling to spend the time growing or producing the bean.
As a result, they are usually used in espresso blends. Poor quality crops may be used in flavored drinks or added to freeze-dried coffees.
Robusta does have about 50% more caffeine than Arabica. Although not as much Robusta is grown. It is typically cheaper than Arabica as it is more resistant to disease and has a higher yield.
Throughout the world, over 65% of coffee is made with Arabica. But that is not enough to guarantee a great cup.
Make sure you use fresh coffee and brew to the taste you want, but don’t ignore Robusta; you can get some good ones.
What is Coffee Environmental Conditions
The coffee plant requires specific environmental conditions to flourish. And produce good berries that can then be changed into the coffee you love.
The coffee berry comes from a tropical plant and usually grows between 25 degrees north and 25 degrees south of the equator.
Tropical environments offer the best conditions for plant growth. Temperatures between 15-24 Celsius (59-75 Fahrenheit) for Arabica, and 24-30 Celsius (75-86Fahrenheit) for Robusta which prefers the hotter drier conditions. Care has to be taken not to subject them to temperatures below 15 Celsius (59 Fahrenheit).
Cold and frost can be a real threat to coffee plants. Although not usually a problem at these latitudes the possibility needs to be taken into consideration at the higher elevations.
Arabica can grow at higher altitudes above 800 meters (2600 feet); Robusta prefers elevations below this level. Different countries and even regions within countries can produce different characteristics.
It is inappropriate to say one country is better than another as it is a matter of an individual’s taste. Try several regions, and identify the ones you like; some of the most popular are Columbian, Hawaiian, and Ethiopian. Brazil and Vietnam are two of the world’s biggest producers.
What is Coffee Planting
When the coffee cherry is picked to be turned into coffee. Some seeds need to be used for future coffee production.
These seeds can be planted immediately or dried and kept up to a year before planting. There are basically two ways to germinate the seeds.
Spread them on a sand bed and cover with moist burlap bag sacks or straw. When radicals emerge, remove the seeds immediately.
The second method is to mix the seeds with moist vermiculite or expanded polystyrene and keep in a polyethylene bag.
Seedlings grow in nursery bags or polyethylene bags. Then planted in the field when they reach 20-40cm (8-16 inches) in height.
What is Coffee Harvesting
The process from planting to harvesting usually takes between three and four years, depending on the variety of the coffee tree.
When it is ripe, the cherry turns a bright deep red.
Most areas that grow coffee are in mountainous regions, and therefore it has to be picked by hand. There are exceptions. In Brazil which can use mechanical systems due to the vast size and relative flatness of some fields.
Once ripe, you only have a couple of weeks to pick the cherries or become too ripe. There are two ways to harvest coffee, strip, and selective.
Strip picked is where the entire crop is “stripped” of its beans all at the same time.
Selectively picked, as the name suggests, only the ripe cherries are harvested by being picked individually.
It is a very labor-intensive process, every eight to ten days picker rotate among the trees picking the ripest cherries.
This results in more cost and is therefore used mainly to harvest finer Arabica beans.
Why are coffee beans sometimes referred to as green beans? As you can see from the picture un-roasted, coffee beans have a greenish color.
What is Coffee Processing?
When the coffee bean is ripe, it is time to remove the bean, surrounded by skin and pulp.
There are two methods used to get the bean from the pulp surrounding it. The dry method, and you guessed it the wet method.
The dry method is popular in dryer countries producing Robusta coffee such as Brazil, Ethiopia, Haiti, and Paraguay.
90% of Arabica is processed using the dry method. Wet or humid environments prefer to use the wet method.
The oldest method is dry processing. During the drying of the pulp ferments giving the bean its taste. The environment used to dry the beans. The settings of the machine can also affect the taste of the bean.
What is Coffee Processing Dry Method
The dry method involves three steps sorting/cleaning, drying, and hulling. The sorting and cleaning include separating the ripe, overripe, and damaged cherries. Removing leaves, twigs, and soil, this is all done by a method known as winnowing.
A large sieve is used to do the initial separation, and then hand pickers remove any remaining unwanted “stuff.”
A flotation method can also be used.
All the cherries are placed in a big vessel of water. The ripe cherries rise to the top and are then skimmed off.
Drying the cherries involves placing them on waist-high benches. Or laid out on brick/concrete patios, occasionally being turned to dry evenly.
Depending on the weather conditions. This can take up to four weeks, the cherry cannot have a moisture content higher than 12.5%.
Machines can be used to speed up the process. Once the cherries have initially been dried under the sun for a few days.
Drying the beans too much can make them brittle, causing them to break during the hulling process.
Too much moisture and the beans become susceptible to attack from bacteria and fungi. Drying is considered to be the most critical part of this three-step process.
Hulling is where all of the cherry’s outer layers are removed to release the beans; machines are usually used for this step.
What is Coffee Processing Wet or Washed Method
The wet method is mechanical and uses a lot of water; it is kinder to the bean and produces a better quality of finished product and therefore, can demand higher prices.
The process involves cleaning, separating, drying, and curing the cherry. The first part in the process is like the dry method. The cherries are cleaned and sorted to get at the ripe cherries.
The next part of the process is the main difference between the two methods.
The bean is separated from the rest of the cherry before drying. It all starts by separating the outer skin from the pulp and bean by squeezing the cherries. Care must be taken not too squeeze too much and damage the bean.
Vibrating screens are then used to remove the pulp; this doesn’t remove all the pulp, a thin film is usually left on the bean.
The bean is put into a large tank and left to ferment. Where nature is left to take its course and breaks down the remaining layer of sticky flesh.
This process can take between 24 and 36 hours. and care must be taken to ensure the coffee does not get any nasty taste from the fermentation process.
The coffee bean is now washed and has to be dried from its moisture content of around 57% to the required 12.5%. Once again we go back to the same method used in the dry method.
Curing is the final step, and this is where the parchment is removed from the bean.
After the dry or wet method, the bean is cleaned, screened, and graded before being sold.
Bags are typically sold in 20kg bags, although some are available in 15kg bags.
There is also a process where the outer skins are removed. The pulp is allowed to dry on the bean, the beans are then hulled as in the drying process.
This is known as semi-washed. The processing method results in different characteristics for the beans. Dry has an enhanced body and complexity, wet enhances clarity and acidity, semi-washed tries to combine both.