How coffee beans are processed | From Seed to a Cup

The coffee you enjoy each day has taken a long journey to arrive in your cup.

Coffee is one of the biggest commodity to trade worldwide and many of us consider it as a necessity and part of our lives to begin our day. In fact, coffee is processed in a long way until it is served in your lovely cup. In this article, we will discuss its journey so you will have more cups of coffee every day after this.

Between the time they’re planted, picked and purchased, coffee beans go through a typical series of steps to bring out their best.

1. Planting The Seed

A coffee bean is actually a seed. When dried, roasted and ground, it’s used to brew coffee. If the seed isn’t processed, it can be planted and grow into a coffee tree.

Coffee seeds are generally planted in large beds in shaded nurseries. The seedlings will be watered frequently and shaded from bright sunlight until they are hearty enough to be permanently planted. Planting often takes place during the wet season, so that the soil remains moist while the roots become firmly established.

2. Harvesting and Picking

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.  

There is typically one major harvest a year. In countries like Colombia, where there are two flowerings annually, there is a main and secondary crop.

3. Sorting and Selecting

There are two steps in sorting and selecting:

First Step: Removing Debris, stones, and twig.

Second Step: Berries are thrown into a water tank to remove unripe ones which float at the surface.

4. Pulping the Cherries

Getting rid of the skin and the pulped fruit (mucilage) that surrounds the beans.

In most countries, the crop is picked by hand in a labor-intensive and difficult process, 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.

5. Fermenting

Breaks down the sugars in the mucilage to produce acids that are responsible for the depth and complexity of the coffee.

Depending on location and local resources, coffee is processed in one of two ways:

The Dry Method 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. In order to prevent the cherries from spoiling, they are raked and turned throughout the day, then covered at night or during rain to prevent them from getting wet. Depending on the weather, this process might continue for several weeks for each batch of coffee until the moisture content of the cherries drops to 11%.

The Wet Method removes the pulp from the coffee cherry after harvesting so the bean is dried with only the parchment skin left on. First, the freshly harvested cherries are passed through a pulping machine to separate the skin and pulp from the bean.

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.

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. 

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.

6. Drying

Coffee beans need to dried until moisture content is around 9.13%.

If the beans have been processed by the wet method, the pulped and fermented beans must now be dried to approximately 11% moisture to properly prepare them for storage. 

These beans, still inside the parchment envelope (the endocarp), can be sun-dried by spreading them on drying tables or floors, where they are turned regularly, or they can be machine-dried in large tumblers. The dried beans are known as parchment coffee, and are warehoused in jute or sisal bags until they are readied for export.     

7. Storing

In this stage, coffee can be stored for several months or years depending on the temperature and humidity.

8. Milling

All other layers still surrounding the beans are being removed. The two steps in the milling process are hulling and polishing.

Before being exported, parchment coffee is processed in the following manner:

Hulling machinery removes the parchment layer (endocarp) from wet processed coffee.  Hulling dry processed coffee refers to removing the entire dried husk — the exocarp, mesocarp and endocarp — of the dried cherries.

Polishing is an optional process where any silver skin that remains on the beans after hulling is removed by machine. While polished beans are considered superior to unpolished ones, in reality, there is little difference between the two.

9. Grading or Cupping

Professional coffee graders classify the coffee bean quality by their “primary and secondary defects”.

Grading and Sorting is done by size and weight, and beans are also reviewed for color flaws or other imperfections.

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.

10. Distributing

Coffee is being shipped to where it’s needed. Direct trade and fair trade to support farmers and customers.

11. Roasting

Roasting transforms green coffee into the aromatic brown beans that we purchase in our favorite stores or cafés. Most roasting machines maintain a temperature of about 550 degrees Fahrenheit. The beans are kept moving throughout the entire process to keep them from burning.

When they reach an internal temperature of about 400 degrees Fahrenheit, they begin to turn brown and the caffeol, a fragrant oil locked inside the beans, begins to emerge. This process called pyrolysis is at the heart of roasting — it produces the flavor and aroma of the coffee we drink.  

After roasting, the beans are immediately cooled either by air or water. Roasting is generally performed in the importing countries because freshly roasted beans must reach the consumer as quickly as possible.

The roasting process is the final step that results the flavor when you brew. There are several types of roasting profile with specific coffee menu to brew. The flavor of a roast depens on the time and temperature of roasting. Light roasted beans still taste mainly fruit and floral when medium roast coffees are the usual used-profile to take on some flavors of caramelization without losing the origin taste. Lastly, the dark roasted coffees has the toasted flavor notes and full body which is suitable for making espresso.

12. Packaging

To protect the beans from air and moisture and to stay fresh for weeks the packing should be sealed well.

13. Grinding

After the beans are roasted and stored for several days, you may grind them based on your preferred grind size and the type of coffee you would drink. It will affect how your hot water extracts the essence of coffee.

Grinding coffee goes stale within hours so coffee beans should be grind right before brewing.

The objective of a proper grind is to get the most flavor in a cup of coffee. How coarse or fine the coffee is ground depends on the brewing method.

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.

Are you still curious about how to grind coffee beans? Check out our article

14. Brewing

Brew temperature, grind size and the right coffee to water ratio are key factors to the perfect cup of coffee.

Everyone serves their coffee in various ways, especially in brewing step, but remember that coffee is more than just final brewing process. Hopefully by reading this article, you starts more various coffee on your cup and concern more on the process.

15. Drinking

The next time you’re enjoying your coffee, cold brew, or cortado, spare a thought for the amount of hard work that went into getting it to you.

Let’s enjoy the coffee!

Do you know the nutrition of the coffee? Check out our article!

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