Farm to Cup
We consume over 2.25 billion cups of coffee all around the globe, every single day. An estimated two-thirds of U.S. Americans drink a cup of coffee every day, and those that do total up 18.5 gallons of the brew a year – but that’s nothing compared to Finland, where people drank on average 3 times as much.
1. Growing Coffee
Coffee takes a lot longer than ten minutes to make. An unroasted green coffee bean is actually the seed of a coffee plant (genus Coffea). There are several species of Coffea plants, with the most common being the Coffea arabica, responsible for 75-80% of global coffee production, while Coffea canephora, aka robusta is responsible for approximately 20% of global production.
It takes approximately 2.5 months for a fresh seed to germinate into a plant, while older seeds can take up to 6 months to germinate. Young coffee plants can be quite fragile and so are usually kept under shade cloth to protect them from the elements.
It then takes about 3-4 years for a coffee plant to begin producing fruit that can be harvested for quality coffee. The plants produce flowers that develop into coffee cherries over a period of between 30-35 weeks.
2. Harvest and Processing Coffee Cherries
Depending on the variety, it will take approximately 3 to 4 years for the newly planted coffee trees to bear fruit. The fruit, called the coffee cherry, turns a bright, deep red when it is ripe and ready to be harvested. Most coffee-producing countries have an annual harvest, although some countries like Colombia have two flowerings each year, resulting in two harvests.
Harvesting coffee remains very labor intensive in many countries and is often done by hand. This is often the case because the trees are grown in developing countries where labor costs are cheap or the terrain is too difficult for machinery to operate on.
Though in places like Brazil where the landscape is relatively flat and the coffee fields immense, the process has been mechanized. Whether by hand or by machine, all coffee is harvested in one of two ways:
Strip Picked: All of the cherries are stripped off of the branch at one time, either by machine or by hand.
Selectively Picked: Only the ripe cherries are harvested, and they are picked individually by hand. Pickers rotate among the trees every eight to 10 days, choosing only the cherries which are at the peak of ripeness. Because this kind of harvest is labor intensive and more costly, it is used primarily to harvest the finer Arabica beans.
A good picker averages approximately 100 to 200 pounds of coffee cherries a day, which will produce 20 to 40 pounds of coffee beans. Each worker's daily haul is carefully weighed, and each picker is paid on the merit of his or her work. The day's harvest is then transported to the processing plant.
So how does harvesting happen? The farmer will know the coffee cherries are ready to be harvested when they turn bright red. They are then either stripped from the branch or selectively picked. If they are stripped the picker simply pulls their hand along the branch, pulling all the beans to the ground, regardless of color. Green cherries can be included in the harvest but will negatively impact the taste of the coffee if processed with the ripe ones.
If the cherries are being selectively picked, the pickers will generally return to the tree again several days later to harvest any additional cherries that have since ripened.
3. Processing the Cherries
Once the coffee has been picked, processing must begin as quickly as possible to prevent fruit spoilage.
The coffee cherry is a coffee bean surrounded by a silver skin, a parchment layer, a pectin layer, a pulp layer, and the outer skin, meaning that these outer layers must be removed. It has to be done quickly after the harvest in order to avoid spoilage.
Depending on location and local resources, coffee cherries can be processed in multiple ways, but two of the most common include:
is the age-old method of processing coffee, and still used in many countries where water resources are limited. The freshly picked cherries are simply spread out on huge surfaces to dry in the sun. The cherries are then placed on a concrete or brick surface to dry in the sun, and regularly manually turned by hand to ensure even drying. The process is complete after 4 weeks until the moisture content of the cherries drops to 11%.. This method is often used in sunny climates including Ethiopia and Brazil.
The cherries are covered at night or during rain to prevent them from spoiling.
This method removes the fruit covering the seed before drying begins. This requires substantial amounts of water and specific types of machinery. When the cherries are submerged in water, some of the unripe and damaged fruit will float so it’s easy to detect.
The skin of the cherry, and some pulp, is removed by pushing the submerged cherries through a depulper. The fruit is then either fermented with microbes to break down the pulp or the fruit is mechanically scrubbed to scrape off the pulp.
If fermentation is used, it must be carefully monitored so that the coffee bean does not take on any undesirable flavors. The wet-processed cherry is left with the silver skin and the parchment layer still surrounding the bean, which is generally dried to circa 10-12% moisture after the wet process is performed.
After separation, the beans are transported to large, water-filled fermentation tanks. Depending on a combination of factors -- such as the condition of the beans, the climate and the altitude -- they will remain in these tanks for anywhere from 12 to 48 hours to remove the slick layer of mucilage (called the parenchyma) that is still attached to the parchment. While resting in the tanks, naturally occurring enzymes will cause this layer to dissolve.
While these are the two most common processing methods, they’re not the only ones.
Then the beans are separated by weight as they pass through water channels. The lighter beans float to the top, while the heavier ripe beans sink to the bottom. They are passed through a series of rotating drums which separate them by size.
When fermentation is complete, the beans feel rough to the touch. The beans are rinsed by going through additional water channels, and are ready for drying.
4. Milling the Beans
The farmer’s removed some parts of the cherry, but not all. So next the coffee beans are placed in a hulling machine; this removes the parchment layer from the wet-processed coffee or the entire dried husk from dry-processed coffee.
At this point, the beans will still have their silver skin on them and they may be polished to remove that skin. This step is optional but polished beans are typically considered superior to unpolished.
The coffee beans are then graded and sorted. Beans are sized by being passed through a series of screens. They are also sorted pneumatically by using an air jet to separate heavy from light beans.
Typically, the bean size is represented on a scale of 10 to 20. The number represents the size of a round hole's diameter in terms of 1/64's of an inch. A number 10 bean would be the approximate size of a hole in a diameter of 10/64 of an inch, and a number 15 bean, 15/64 of an inch.
Finally, defective beans are removed either by hand or by machinery. Beans that are unsatisfactory due to deficiencies (unacceptable size or color, over-fermented beans, insect-damaged, unhulled) are removed. In many countries, this process is done both by machine and by hand, ensuring that only the finest quality coffee beans are exported.
Beans that are small in size or blemished might be rejected during this process. Millers also remove beans that are insect-damaged or over-fermented.
5. Exporting the Beans
The milled beans, now referred to as green coffee beans are now ready to be exported or sold within the domestic market. The size of the global coffee export market is staggering – there is an estimated 5 million people employed in the coffee growing and processing industries worldwide
Then loaded onto ships in either jute or sisal bags loaded in shipping containers, or bulk-shipped inside plastic-lined containers. World coffee production for 2015/16 is forecast to be 152.7 million 60-kg bags, per data from the USDA Foreign Agriculture Service.
Yet just because it’s ready for export doesn’t mean that it’s ready to drink just yet…
6.Tasting and Grading
The green beans are often roasted in small batches and sampled by tasters to ascertain the quality of the bean. Beans are also rated on the quality of their appearance, aroma, and color. Tasters may decide to blend batches and even different varieties to obtain certain qualities, although others will remain single origins.
Coffee is repeatedly tested for quality and taste. This process is referred to as cupping and usually takes place in a room specifically designed to facilitate the process.
First, the taster — usually called the cupper — evaluates the beans for their overall visual quality. The beans are then roasted in a small laboratory roaster, immediately ground and infused in boiling water with carefully-controlled temperature. The cupper noses the brew to experience its aroma, an essential step in judging the coffee's quality.
After letting the coffee rest for several minutes, the cupper breaks the crust by pushing aside the grounds at the top of the cup. Again, the coffee is nosed before the tasting begins.
To taste the coffee, the cupper slurps a spoonful with a quick inhalation. The objective is to spray the coffee evenly over the cupper's taste buds, and then weigh it on the tongue before spitting it out.
Samples from a variety of batches and different beans are tasted daily. Coffees are not only analyzed to determine their characteristics and flaws, but also for the purpose of blending different beans or creating the proper roast. An expert cupper can taste hundreds of samples of coffee a day and still taste the subtle differences between them.
7. Roasting the Coffee
Now the green beans are roasted in mass and at high temperatures. Yet there are a wide variety of temperatures and durations beans might be roasted at, all of which enhance specific qualities in the bean.
Coffee roastmasters develop different roast profiles for coffee beans from different sources. The bean’s region, variety, processing method, and desired flavor characteristics will all play a part in determining how a bean should be roasted.
Some of the most common roast profiles you’ll come across are:
Underdeveloped sweetness, grassy, and acidic
Light brown, retains original characteristics of bean and complex acidity
Medium light brown, character of the bean is still preserved
Full City Roast
Medium dark brown, roast flavor prominent
Moderate dark brown, surface oil, bittersweet flavor, low acidity, original characteristics of bean muted
Dark brown, shiny, burnt undertones, original flavor of bean hard to taste
Nearly black, very shiny, no/low acidity, thin body
Please note: these are merely parameters.
Everyone has different roasting preferences but in the specialty world, the lighter the roast the better.
8.Grinding the Coffee
And you’re nearly ready to drink your coffee! The roasted coffee is next ground to a coarseness appropriate for the brewing method that will be used. For example, an espresso machine will require a finer coffee grind than a French press.
The length of time the grounds will be in contact with water determines the ideal grade of grind Generally, the finer the grind, the more quickly the coffee should be prepared. That’s why coffee ground for an espresso machine is much finer than coffee brewed in a drip system.
Espresso machines use 132 pounds per square inch of pressure to extract coffee.
We recommend taking a moment to examine the beans and smell their aroma — in fact, the scent of coffee alone has been shown to have energizing effects on the brain.
9. Brewing Coffee
There are many ways to brew coffee including:
Drip over/ Chemex / Siphon / V60 / AeroPress / French Press / Espresso Machine
Each way of brewing coffee can greatly impact on the flavor of your cup. Part of the fun of coffee is experimenting with different roasts, grinding techniques, and brewing methods to discover the true variety of coffee.