From Bean to Cup

Plantations, The Beginning

Coffee plantations around the world are located mainly in Tropical Africa, Asia and America. These places have ideal climatic conditions, with temperatures ranging from 17 to 30 degrees Celsius and annual rainfall measuring between 1200 and 2000 millimeters. The coffee plantation requires soil rich in humus, nitrogen and potassium, and grows at an altitude of up to 2500 meters. The plants also need to be constantly watered and fertilized to ensure that they have all the nutrients responsible for their high quality.

The seeds usually sprout after 8 or 10 weeks after planting, and are immediately transferred to plastic containers, where they spend up to 12 months in greenhouses or places protected from direct sunlight, until they reach 30 centimeters. At that point, they are transferred to the actual plantation. This planting style is common in countries like Brazil, India and places in Central America, as they are places that have large open spaces, in which large machines and irrigation systems can be used.

The coffee plant starts to bear fruit after two or three years, and the number of times this happens depends a lot on the cultivation technique. In the intensive cultivation technique, the plants are exploited to give their maximum and last up to 15 years. On the other hand, in India, in extensive plantations, the plant can live up to 50 years.

The Flower of Coffee, Arabian Jasmine

The coffee flower is extremely interesting. Anyone who has had the opportunity to observe a coffee plantation in bloom knows that they have a very characteristic odor, reminiscent of jasmine flowers. For this reason, the plant used to be called “Arabian Jasmine” around the 17th century.

​The most fascinating thing is that the flower can give some indications of how the quantity and quality of the harvest will be. In countries that produce a lot of coffee, as is the case of Brazil, this characteristic is very important to dictate the rules of price and market development. However, the flowers die relatively quickly and can only be pollinated for a few hours. Factors such as frost or excessive rain can also considerably reduce the number of flowers in a coffee plantation, as they are extremely sensitive.

The Harvest, Stripping and Picking

For the coffee to be of extremely high quality, it is necessary that only the fruits that are already completely ripe are harvested, since fruit beans that are still partially green or even those that are overripe compromise the final taste of the coffee. The different types of crop that can be used are:

Stripping

In the case of stripping, all fruits are removed from the branches, regardless of how ripe they are. This means that a second selection will have to be made after the end of the first process. Water is used to facilitate the separation process, since ripe and unripe fruits have different densities. There is manual and mechanical stripping. The mechanic is the most used in Brazil (in Paraná and São Paulo), because the plantations have to be straight, for the big machines to move between the plants. The branches are gently shaken by flexible paddles, adjusted to make only the ripest beans fall from the branches.

​Picking

Picking is used, for example, in Central America, Kenya, Ethiopia, India and Brazil (Minas Gerais, Espírito Santo and Bahia due to the difficulty of the terrain), and consists of harvesters or pickers walking through the plants at regular intervals, picking up the fruits one by one and selecting those with the highest degree of ripeness. This method is expensive and time-consuming, but it delivers very high quality coffee.

Improvement, Grain Processing

The improvement is the whole process that comes after the harvest, until the roasting. It starts with grain processing. Processing needs to be done immediately after harvesting as the beans need to be extracted from the husk within a few hours or else they will start to ferment or even rot, giving the coffee an extremely unpleasant taste. Before extraction, then, the grains need to be separated from foreign objects such as small stones, leaves and sticks. This process can be done with the help of sieves or even air jets.

There are basically two systems to extract the grain:

The dry processing that gives rise to the so-called “natural coffee”, in which the cherries are left to dry in wide spaces, in a layer no larger than 3 centimeters. This layer has to be turned constantly (from 15 to 20 times a day), so that the process is uniform. After that, they are placed in mechanical dryers, which speed up the process.

Wet processing (which gives rise to so-called “washed coffee”, in which the cherries are placed in compartments, where the skin and part of the inner part of the cherry are removed. The seeds are then left to ferment for a few hours.

​It is also important to emphasize a third method, widely used in Brazil, the peeling method, which is between wet and dry. Instead of letting the beans ferment, they are left in the sun to dry, without any other processing methods.

​Regarding transport, depending on where the coffee goes, it has to face a long journey, often crossing oceans and going through several temperature variations to reach its destination.

Coffee is usually packaged in 60kg bags made from a natural material that allows the contents to breathe. All bags come with the weight, origin and port of shipment stamped and the coffees are stored in dry and well-ventilated places. The grains are then transported by sea, truck or rail and 95% of them arrive in Europe in large containers, which can be of the standard type or even refrigerated. It is extremely important that the grains are protected from rain, moisture and excessive cold and heat.

The Roast, Flavour and Aroma

Roasting is the most important part of the whole process, as it is only after the grain has been roasted that it shows the characteristics that distinguish it when it comes to drinking. During this process, chemical and physical reactions produce more than a thousand substances, each of which contributes in a certain way to the taste and aroma of coffee.

There are 3 stages in the roasting process: drying, which eliminates residual moisture from the grain, roasting itself and cooling. The weight of the bean decreases by about 16% during roasting and its volume increases by 60%. The sugars are caramelized and the water evaporates, causing a reaction between the sugar and the proteins, thus creating the pigment that gives the coffee its characteristic color, in addition to developing the aroma.

Coffee roasting is considered an art, as the final taste and aroma depend on the temperature curve used. Each type of roast follows a specific curve, for example, lower temperatures produce a coffee with a lighter color, not as bitter and with a pleasant acidity content; Higher temperatures, on the other hand, produce a darker, more bitter coffee with a more intense flavor.

The Grinding, Final touch

The extra fine grind

The extra fine grind of the coffee beans must be used in the preparation of Turkish coffee, as the coffee powder is not strained. This type of coffee is prepared in a Turkish pot (ibrik), where ground coffee beans are mixed with hot water and sugar. This is an exclusive type of grinding that makes it possible to extract a unique and original cup of coffee.

​The fine grinding

The fine grinding of coffee beans should be used in espresso coffee machines as it makes it possible to prepare a full-bodied and creamy coffee, in the good Italian way. It is a type of grinding that is often used in the extraction of an espresso coffee, as the fine grains offer greater resistance to the passage of hot water, enhancing the flavors and aromas of the coffee. The ideal preparation time for an espresso coffee is 25 to 30 seconds and if the coffee takes more or less time to be extracted, it is necessary to adjust the grinding of the beans.

The medium grind

Medium grinding, as its name implies, is located between fine grinding and coarse grinding of coffee beans. This is a type of grinding that must be used in the preparation of coffee with a French press. By using ground coffee beans with a medium thickness, you will be able to prepare a smoother and more flavored coffee. The French press method forces hot water to come into contact with the ground coffee beans for a maximum period of 3 minutes and that time is enough for all the main characteristics of the coffee beans to be absorbed.

The coarse grinding

Coarsely ground coffee beans should be used to prepare a moka pot coffee. This grinding method allows the extraction of a tasty, strong and full-bodied coffee. Ground coffee beans are placed in the coffee filter, where the water rises and absorbs all the main aromas and flavors of a particular type of coffee.

The Extraction, Preparation Methods

Flavor extraction rate

Larger (coarse) grind sizes need more water contact time to extract the best flavor. Smaller (finer) grind sizes require less contact time to extract the best flavor. In general, we use a coarser grind for longer brew times (4-8 minutes) and a finer grind for shorter brew times (1-4 minutes).

Water flow rate

A coarse grind allows water to pass through quickly. A fine grind slows down the flow of water.

How to perceive grinding

An effective way to communicate and assess grind size is how it feels to the touch. Take a sample of ground coffee and rub it between your thumb and fingers. The coffee is ground into particle sizes ranging from something akin to kosher sea salt for a coarse grind, sand for a medium grind, and powdered sugar for a fine grind.

How to prove

Ultimately, it all comes down to taste. Taste is very subjective. Assuming all other essential manufacturing variables are on the line, simply ask: Is the beverage tasting bitter, astringent, or too strong? Adjust coarser grind next time. Does the drink taste weak, watery, flat or sour? Adjust finer grind next time. Small tweaks make big differences. Keep fine tuning at first, then keep tweaking to find the sweet spot.