Calling myself a coffee expert might sound like a bit of an overstretch, but it’s fair to say I’ve savoured enough coffee over the years to develop a certain reverence for the art of roasting. The flavour, aroma, and texture of a perfect cup of coffee can transform your entire day, and these elements are all intricately tied to the quality of the roasting process.
The history of coffee roasting dates back to the 15th century, and the procedure has come a long way since then. However, the essence of the process remains the same. Roasting coffee beans involves heating the beans until they’re fully cooked and have undergone a chemical transformation that makes them ready for brewing.
Coffee roasting is a delicate balance of time, temperature, and intuition. It requires precision and experience to get right every time. From the type of beans you choose to the roast level, there are plenty of factors to consider.
First of all, it’s important to choose the right type of coffee bean. Arabica beans are the most commonly used bean globally, and they’re known for their subtle flavours and lower acidity. Robusta beans, on the other hand, are higher in caffeine and bitterness but can be more affordable.
Once you’ve chosen your beans, it’s onto the roasting process. Coffee roasting machines come in all shapes and sizes, but they all work on the same principle of heating the beans to a specific temperature and time. Roasting can be done at different levels; light, medium, and dark roast. Each level will create a different taste and aroma.
A light roast is relatively mild, with little to no oil on the bean. This roast preserves the natural acidity and sweetness of the coffee, making it ideal for fruity and citrusy coffee flavours.
With a medium roast, the roasting process develops more of the coffee’s flavours and oils. These beans tend to have a good balance of sweetness and acidity, creating nutty and chocolatey notes in the cup.
Finally, a dark roast is intense and full-flavoured. This roast method results in a deep, rich colour with plenty of oils on the bean, creating a slightly bittersweet taste profile. These beans are commonly used for espresso and other strong coffee drinks.
To achieve a perfect roast, you’ll need to pay attention to time, temperature, and the colour of the bean. Coffee roasting is an art that requires a skilled artisan to identify when the beans are ready to be removed from the roaster. Over-roasting can result in a burnt taste, while under-roasting will leave the coffee with grassy or vegetal flavours.
The perfect roasting process is a mix of science and art. While the science behind coffee roasting involves the chemical reactions that the beans undergo during roasting, the art is in knowing exactly when to stop the process. The carmelisation of the natural sugars in the bean is the key to achieving the perfect balance of sweetness, acidity and bitterness.
The roast level also has a significant impact on the coffee we drink. The oils and flavours in the coffee bean are unlocked through the heating process. The roast level dictates the strength of these oils and the associated flavour notes.
For a light roast, the oils in the coffee bean are just developing, which means the coffee is generally lighter in body and has a higher acidity level. This type of roast is characterised by the fruity, floral, and citrusy notes that shine through in the flavour profile.
Medium roasts are slightly darker, with the oils beginning to become more prominent in the coffee bean. This roast level gives a balance of acidity and flavour profile. With more of the oils break down, medium roasted coffee can take on nutty, caramel and toffee notes, while still retaining a bit of the fruitiness and acidity from the light roast.
Finally, dark roasts are well past the development of the oils in the coffee bean. They have a heavier mouthfeel and are bolder in their flavour profiles. Customer preferences for darker roasts range from earthy, smoky and woody, to more of the chocolate and caramel sweetness from a medium roast.
Coffee roasting is as much science as it is artistry. Creating the perfect roast requires precision, knowledge, and skill. A great coffee roaster should be able to assess every detail of the roasting process, from the onset of the roast to the point where the beans have the right balance of flavour.
Ultimately, the taste and aroma of a freshly brewed coffee depend on the roasting process. The roast level, the beans chosen, and the care taken in the roasting process combine to create a whole experience that can make or break the coffee drinkers day. With that in mind, choosing your roaster carefully is key to extracting the best flavour from your coffee beans. And with so much involved in the process, it’s no wonder coffee roasting is considered an art. Who knows, perhaps with the right knowledge and skills, you could become a coffee expert yourself.