From Bean to Brew: How is Coffee Made?
While brewing methods contribute a great deal to your resulting coffee’s flavour, there is much more to your coffee than the way it is brewed. The beans have been on a long journey before they reach your cup, and each step of this journey has had an impact on the resulting brew. We take a look at how your coffee is made from seed to cup.
Coffee beans are seeds, which, if left unprocessed, can be planted and grown into a coffee tree. Unprocessed means that the bean hasn’t been dried, roasted or ground to make a tasty brew, so you cannot grow coffee from a bean that has been roasted. Coffee seeds will typically start off in a shaded nursery, receiving frequent watering, before being permanently planted in moist soil to grow. It will take approximately four years for a coffee tree to grow enough to bear fruit.
Coffee beans come from the coffee cherry, which grow on the tree. When they are ready to be harvested, the coffee cherry will be a deep red colour. Usually, there will be one main harvest a year. However, in countries with ideal environments, such as Colombia, there may be a main and secondary crop each year. Most countries will see these cherries picked by hand, as the landscapes on which coffee is grown are generally not suited to the use of machinery. However, many Brazilian coffee plantations will use machinery, as the coffee fields are typically vast and comparatively flat.
Coffee cherries can be strip picked or selectively picked. Strip picking involves removing all of the cherries from the tree at once, either by machine or by hand. Selective picking is done by hand, with pickers visiting the trees every week or so to pick only the ripe cherries. This process is far more labour intensive and costly than strip picking, so it is usually reserved for the quality Arabica beans. Good coffee pickers will bring in around 150 pound of coffee cherries a day, which equates to around 30 pounds of coffee beans.
After the coffee cherries have been harvested, they will be sent off to be processed as soon as possible to ensure the coffee is fresh. The beans can be processed using either the dry or wet method, depending on water resources available.
In dry processing, the cherries will be laid flat in the sun and left to dry out until the moisture levels drop to 11 percent. The cherries will be raked and turned to ensure an even dryness. They are covered at night and in bad weather to keep them dry. The dry method for processing can take a number of weeks to complete, depending on the weather.
On the other hand, the wet method uses water to help sort and prepare the beans. First, the coffee cherry skin and pulp is removed from the bean in a pulping machine. The beans are then passed through water channels, where the light beans float, and the heavy beans sink, allowing for the beans to be separated by size. The beans will be left to soak for between 12 and 48 hours to remove the remaining layers around the bean, known as parenchyma.
If the beans have been processed using the wet method, then they will need to be dried. The beans will need to be dried to around 11 percent moisture. This can be done by spreading the beans out to be sun-dried, or they can be dried by machine in a big tumbler.
The next step is to mill the beans. The beans must first be hulled to remove any remaining layers around the bean itself. For wet method beans, this is simply removing the endocarp – the innermost layer that surrounds the seed. For dry method coffee beans, the hulling process refers to the removal of the entire dried cherry husk, leaving only the coffee bean behind. At this point, the beans may be polished by machine, although this process is optional and does not particularly add to a bean’s quality.
The beans will then be graded and sorted depending on their size, weight, colour and imperfections. Any beans that are unsatisfactory, due to defects such as damage, remaining unhulled, poor size or colour and being over-fermented will be removed.
Milled beans, known as ‘green coffee’ is then placed in jute sacks and loaded into shipping containers to be exported by boat to roasters around the world.
Coffee beans will typically be roasted in the country the beans are imported into, as freshly roasted beans need to get to the consumer as soon as possible for the best coffee experience. The roasting process turns the green beans into the aromatic and flavourful coffee that we know and love. Typically, roasting machines will be kept at 290 degrees Celsius, allowing the beans within to reach an internal temperature of 205 degrees Celsius or more. At this temperature, the beans begin to turn brown, and the flavourful and aromatic caffeol oil is released. Beans are then cooled by water or air immediately after roasting. The beans will be bagged up and sent to coffeehouses, shops or direct to coffee-loving consumers!
The next step for producing quality coffee is a good grind. Coffee needs to be ground to get out all of the intense flavours packed within the bean. The brewing method you choose to use will impact on how fine or coarse you need to grind your coffee. This is usually down to how long the coffee will be in contact with water and how quickly it is prepared. For example, an espresso machine will use much finer coffee grounds than a drip brew coffee maker.
After a long journey from seed, your coffee is finally ready to be brewed! There are many methods for you to choose from, but naturally, the AeroPress UK is our favourite! Find out how to brew coffee with an AeroPress in our previous blog post!