Everything You Wanted To Know About Coffee Roasting
Everything You Wanted To Know About Coffee Roasting
Feb 16, 2020.
18 minute read
Roasting is a process of converting green coffee beans to brown beans in order to brew aromatic and flavourful coffee. The process is a complete transformation; the beans undergo considerable chemical changes when their internal temperature rises. The heating also caramelizes the bean’s sugar to give them their characteristic brown colour. If you thought coffee is originally found in brown or even green colour, here’s some news: coffee beans are seeds of tiny red fruits. The coffee plant can simultaneously grow flowers and ripe fruits, also called cherries. To extract the inner seed, the fruit’s pulp and skin, both outer and inner, are removed.
The seed, also known as the coffee bean, is then dried, cleaned, hulled and hand sorted and taken for roasting. Without the heating-process, the bean would make a bland tea-like drink without the flavours of the roasting process to produce the inner sugars into caramelization.
Roasting gives the green coffee beans its unique flavour and aroma. High-grade Speciality coffee has sweetness and subtle nuanced flavours which Araku’s skilled roasters cull from the beans. To retain the coffee bean’s sweet spot, acidity and flavours such as florals, chocolate or toffee notes, we maintain precise temperatures and airflow at our in-house roasting unit.
Coffee roasting process
Before being roasted, the green beans have the look of jade and smell of freshly-cut grass. To develop and extract the depth of flavours and a distinct aroma, there is a range of different coffee-roasting techniques, styles, and approaches applied. But mainly, it involves high temperatures (350F to 500F), the variation of airflow, constant visual observation and finally, audible cracks. The roaster uses all senses, eyes, ears, nose and skill which comes from experience which determines the beans final roast profile (light, medium, medium-dark and dark).
Read on for a quick rundown of the coffee-roasting process.
At this stage, while the heat builds, the beans change from green to a slightly yellow colour. The beans would now emit a grassy aroma. Soon the water inside the beans starts to evaporate as steam.
This is where the real roasting begins. Depending on the escalation of temperature and airflow, the beans will produce an audible crack after 6 to 8 minutes. The cracking is similar to the sound of popcorn popping.
This is called a ‘Light Roast’ where the coffee is mild in flavour with bright acidity. At Araku, we roast carefully in order to retain the subtle nuances of the bean’s flavours.
As the coffee bean’s sugar further caramelizes, the beans swell in size for a roast that is both popular and aromatic. The beans are medium-brown in colour with a balanced flavour and acidity. A medium roast adds to Araku MicroClimate's generous body and wholesome notes of almost candied fruit and a hint of elegant bitterness in its finish.
The bean’s flavours further intensify. Medium-dark roasts are rich and dark in colour. Araku’s coffee roasting profiles for Grand Reserve and Signature have been set precisely to find the ‘sweet spot’–where we know our beans taste best.
At this stage, the beans will reach the verge of a second cracking. Araku Selection is roasted slightly more than our other coffees, just on the edge of a second crack to give it a dark roast. Any roast beyond the second crack renders the beans dark-brown to almost black in colour; all subtle nuances of the coffee beans are burned off.
Recognizing coffee roasts
It can take years to become an expert roaster who understands the split-second timing between perfectly roasted coffee and a ruined batch. In order to develop these skills, you may need to invest in a coffee-roasting machine for home use. Additionally, you can always sign up for our SCA certified Roasting course where our international trainers will teach you the nuances of Roasting coffee perfectly.
We have a roast chart that you could use as a quick on-the-go guideline for roasting coffee at home, buying already roasted beans or if you are simply looking to get better at identifying roasts.
Coffee Roast Chart
We cup “taste test” and measure all our roasts using a spectrometer to measure the reflected light of roasted coffee before we sell. For common roast terminology please refer to the below chart.
Each coffee is an individual and requires knowledge of that specific bean. Two coffee varieties grown in different countries and environments might look similar but taste drastically different even when roasted at the same level. A professional roaster curates a “cooking process” and provides a profile of taste we want you to experience. Roast temperature, time and airflow yield a specific shade of brown helps in categorising the beans by its colour as a general guide.
Every step of the way is important in the coffee life cycle. From the earth, to harvest, processing, roasting and finally brewing. There is a chain of quality and if any link breaks along the way, it negates the final impact of your enjoyment of our coffee. Araku’s Speciality coffee creates consistent, smooth, sweet and clean flavours. Each batch of Araku coffee is 100% Arabica and single-origin beans. Araku’s beans feature ethical farming practices, unique flavours and are harvested like wine grapes in one-acre farms.
Coffee beans are Araku’s heart and soul; we take complete care of the beans and the farmers who grow them, they are expertly roasted and finally brewed for your cup, at home or elsewhere and greet you with your favourite coffee experience, ever.