Spotlight On: Coffee Roasting Process
Roasting coffee is an amazing process and the art of the roaster is to find the perfect balance of roasting to bring out the bean’s best aroma and flavour.
Roasting is a very unique skill that can take years to master. It is not as simple as heating up some beans and hoping for the best, there is a lot of skill and precision behind it. The end result can be affected by lots of things, so it is important that the Roaster has a strong foundation of knowledge to ensure the best coffee is produced. Even the weather conditions at the Roastery can affect the end result. The difference between a perfect roast and a ruined batch of coffee can be a matter of seconds!
Coffee beans are stored green to avoid any loss of taste or quality. The coffee roasting process is what creates the characteristic coffee flavour, it brings out the flavour and aroma that is locked inside the green beans. The flavour and taste of any coffee bean depends on the farm it comes from, but ultimately the Roaster has the opportunity to manipulate the coffee to taste how they want. This can be achieved through different styles of roasting, or by blending beans from different farms to create a unique blend. Once roasted, the beans should be used as quickly as possible to ensure the best quality, as over time the flavour can begin to diminish.
The first recorded coffee roasting took place in the 15th Century in the Ottoman Empire. Back then, thin pans made from metal or porcelain were used, rather than the roasting machines we have today. Click here to read more about the history of coffee.
Before any roasting takes part, the coffee cherries are picked, processed and dried into green coffee beans. Depending on the variety, newly planted coffee trees can take up to 3-4 years to bear fruit. The fruit, known as the coffee cherry, turns bright red when it is ripe and ready to be harvested. The beans are then sold on, whether it is to a coffee supplier, or directly to the roaster (Click Here to read more about Direct Trade).
Once the green beans reach the Roastery, it is time to change them from the spongy, green bean, to the dark coffee bean we know and love. The majority of roasting machines operate at around 280-300 degrees celsius, and the coffee beans are kept moving throughout the whole process to stop them burning, similar to a how a tumble dryer dries clothes.
1. The roasting machine heats the green beans, keeping them constantly moving to stop them burning. They begin to turn brown and the aroma and taste begins to change.
2. As the beans continue to be heated, they start to lose moisture and the skin dries out and begins to wrinkle. During this stage is when you will hear the “first crack”. This will make an audible crack/pop sound, and is caused by the increase in pressure inside the bean. The crack alters the structure of the bean and means that the oils inside the bean move to the outer surface. These oils contribute to the flavour of the coffee.
3. If you continue to roast after the “first crack”, the beans will start to caramelise and the beans will start to turn a darker brown.
4. Some coffee blends are roasted even longer than when the beans begin to caramelise. After the beans start to caramelise comes the “second crack”. Similar to the “first crack”, it is an audible noise that occurs as the structure of the bean changes. Beans that are roasted to the second crack are the darkest roasts, and tend to be more bitter than a light or medium roast. Any longer than the second crack and the beans begin to burn.
The beans are closely monitored throughout the process. Not only is the Roaster looking at what the beans currently look like, they are looking ahead and anticipating what the beans are going to be like. A few seconds can be the difference between a perfect coffee and a ruined batch of coffee beans, which is why the skills of the Coffee Roaster can take years to master.
After the beans have been roasted, they are quickly cooled and packed. The sooner they are used after being roasted, the better the taste.
There are three main types of coffee roasts, and different beans are more suited to different roasts. Often, Roasters will combine beans from different origins to create a blend, and they will use their skills and expertise to roast this blend to create the perfect taste.
Light Roasts are stopped before the first crack occurs. There is no oil on the surface on these light brown beans as they haven’t been roasted long enough for the oils to break through. A Light Roast is generally preferred for milder coffee varieties.
With a lighter roast, the taste profile of the coffee’s origin is easier to pick out. It’s much easier to differentiate between an Ethiopian coffee (full bodied, complex) and a Colombian coffee (sweeter, slightly nutty) when it is a light roast, rather than a medium/dark roast.
A medium roast coffee is roasted until just after the “first crack”. They are darker in colour than light roasts and to have more body. Medium roasts tend to have lower levels of acidity than lighter roasts and the roast is likely to be sweeter.
Darkly roasted coffee beans are shiny and dark (sometimes black) with an oily surface and a pronounced, bitter taste. Traditionally, a dark roast was used to mask a low quality bean, but in the right hands, a dark roast can give you a bold, rich coffee. Contrary to popular belief, a dark roast contains the least amount of caffeine, having spent the most time roasting.
Our range of speciality Amokka coffees are roasted in-house at our state-of-the-art Roastery in Denmark. We try out several different roasting profiles on each bean and we roast slowly so that the beans are particularly sweet and aromatic.
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