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What Does a Coffee Roaster Do?
One of the most important steps in the coffee process is the roasting. Check here to know all about it.
Published November 30, 2021
Daniel Hedlund
Coffee experts@The Coffee Lab
Many different steps are involved in the journey of your coffee from plant to cup. However, one of the most important steps in this process is the roasting, which this article will focus on. If you have ever wondered who is coffee roaster and what does a coffee roaster do, then keep reading to find out more and learn more about how coffee roasting impacts the final taste of the coffee that is brewed into your cup.
If you have ever seen a coffee roaster doing what they do, then you will probably know that this process is anything but simple. Roasting coffee requires precision, the right equipment, and is a complex process based on a lot of science to get the final roast just right. Coffee roasters are expert craftsmen who want to get it just right and make sure that they’re getting the best results for the farmers, the customers, and the coffee. When it comes to getting your coffee ready to drink, there is a lot that goes on behind the scenes that coffee lovers aren’t privy to. So, keep reading to learn more about the process of roasting to find out more about what it is and appreciate it more next time you drink coffee.
Where Coffee Comes From
To understand the roasting process, it’s firstly important to understand that coffee comes from around the world. Your organic coffee Chicago isn’t made in a plant – it grows in the plants of the coffee shrub as seeds. Before it even gets to the roasting process, the coffee seeds are planted, grown, harvested, processed, milled, and dried. All of these processes tend to happen in various countries around the world, including South and Central America, Africa, and parts of Asia. Coffee roasters find and purchase these raw coffee beans in two main ways, including:
- Direct Trade: Roasters will use this sourcing model for coffee beans by visiting the farms and meeting the farmers. They will inspect the land and get to know the coffee by trying it on the land that it originates from. This method of sourcing coffee beans is becoming more and more preferred by many coffee roasters today as it eliminates the need for a middleman and allows both farmers and roasters to take advantage of better deals.
- Warehouse and Catalog Sales: Before the growth of direct trade, for several years, the go-to method for sourcing coffee required the roaster to visit a warehouse or order a catalog where they could view what was on offer. Most of the time, a licensed Quality Grader graded and priced the coffees, although samples were sometimes available. Today, this type of sourcing is mostly done online and is much more based on quality compared to in the past.
Making Global Relationships
Direct trade for coffee roasters is about building relationships with coffee producers around the world. Specialty coffee makers think further than simply making as much money as possible. Ethical sourcing has now become much more important than ever before, with more coffee roasters now adhering to direct trade criteria that requires them to buy coffee beans at the Fair Trade price or higher. A good coffee roaster is fully aware of the situations of the farms that they buy coffee from. Despite being one of the world’s biggest cash crops with a high demand for it worldwide, many coffee farms are in poverty. The best coffee roasters proactively use their position to do something about this by listening, learning, and investing in the local communities that they source coffee beans from by always purchasing at a generous rate. Some even go above and beyond this by working with locals to get better them access to clean water, healthcare, education and more. Companies who do this are doing much more than just making money and providing great coffee; they are also having a positive impact on the world, and the coffee trade in general.
The Process of Roasting Coffee
While you can actually get second hand coffee roasters for sale if you are interested in trying your hand at roasting your own coffee, if you are like most people, you probably prefer to buy your coffee pre-roasted, ready to grind and brew it into your favorite mug.
The most obvious thing that a coffee roaster does is heat up coffee beans. However, it’s not quite as simple as throwing some raw coffee beans into a machine, leaving them in to swirl around in the heat for a while, and then pumping out roasted coffee. There’s much more to it.
Coffee roasters need to carefully plan out roasting cycles, as roasted coffee will only stay at its peak freshness for around two to three weeks after roasting. Because of this, coffee roasters need to carefully plan just how much coffee they are going to roast to avoid waste, which can require weeks of preparation and paying careful attention to the supply. Once this has been planned, the actual roasting can begin.
The Science Behind Roasting Coffee
Within the ten to fifteen minutes that it will take to roast a batch of coffee, hundreds of different chemical reactions will take place. This is where the science of roasting coffee comes in, as controlling these reactions can be quite difficult. Any small changes in humidity, airflow, temperature, and time can make huge changes to how the final cup of coffee tastes, so it’s important for roasters to be as precise as possible with the roasting environment and routine.
Roasters will often perform a few sample roasts in a smaller machine that works in the same way as their commercial one, to find the perfect roasting recipe. They will make a note of all the different variables such as the temperature and time to get a closer look at what needs to happen to get the roast just right. They will then wait between 12-24 hours after the sample roasts are complete before they test the coffee’s quality. Throughout this process, known as ‘cupping’, they will take notes to make a careful assessment of the flavor, sweetness, bitterness, acidity, body, aroma, and aftertaste.
Once the roaster has decided on the best roast of the batch, they will do it all over again, sometimes multiple times, in order to make sure that the roast is just right before they roast a commercial-sized batch ready to ship.
The Art Behind Roasting Coffee
If you drink coffee that has been roasted by a particular roaster on a regular basis, then you’ll probably notice something when you switch to another roaster for a while. Coffees tend to take on the personality of their roasters. Roasters have clear style differences, and these can often be noticed when you are drinking their coffee. This is because many roasters know that their craft is an art as well as a science and see the coffee that they roast as being an expression of their personality and values to some degree.
Why Is Coffee Roasting Important?
Before coffee beans can be ground and made into a cup of coffee, they need to be processed and dried. Before they are roasted, the raw coffee beans are greenish-brown and have an earthy aroma – they don’t actually have a coffee scent at all. When coffee is roasted, however, between different aroma compounds are developed, which make the flavor of the coffee.
The Three Main Coffee Roasting Stages
There are three main stages of roasting coffee – the drying stage, browning stage, and development stage.
1. Drying Stage
During this stage, the coffee bean has an 8-12% humidity level. It needs to be dried out further before the beans are ready to roast. This stage will typically last between four and eight minutes using a traditional drum roaster. Typically, at the end of this stage, the temperature of the beans is around 160 degrees Celsius. It’s important to make sure that the beans do not become burned when using a drum roaster, which will happen if there is too much heat at the start.
2. Browning Stage
At the temperature after drying, the beans will have an aroma of hay and toasted bread. As the beans heat up, the aroma precursors are beginning to convert to aroma compounds. The drying continues throughout the browning stage, which also starts the Maillard reaction, which is responsible for the brown color of the beans. Amino acids and reducing sugars react, creating hundreds of different color and aroma compounds. The coffee starts to pop at the end of this stage.
3. Development Stage
The exothermic stage is when the coffee beans start to crack. The aroma compounds that we want for our coffee are developing during this stage. It’s important to slow down the roast now, to avoid getting coffee with a flavor that is too sharp.
While brewing your coffee might only take minutes, there’s a lot of time and effort that goes into getting the roast just right before it’s ready to brew.
About the author
Daniel Hedlund
Working with the Era of We initiative and loves knowledge sharing and a really good cup of coffee.
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