If you don’t have your roasting process down, then your competition could prove to be a tough adversary indeed.
As one could imagine, there are many components that go into roasting a near-perfect coffee. We break down some of these for you, including how the quality of the beans, the drying stage and other factors are crucial to the procedure.
Here are some top tips to help you nail down a roasting process.
1.) Drying
Coffee beans drying by Nestlé via Flikr.
The typical coffee bean has an average humidity of eight to 12 percent. Therefore, it becomes crucial to dry it before the actual roasting process begins. This process typically takes anywhere from four to eight minutes if you were to use a conventional drum roaster. All other things being equal, the temperature during this stage should be around 160 degrees Celsius.
However, it serves to make sure to check whether the beans are burned, as this can be pretty easy to overlook at the onset. In addition, this process is also important because it collects pent-up energy in the bean since the last forthcoming stage is an exothermic process.
2.) Browning
Roasting coffee beans by Hisakazu Watanabe via Flikr.
At this point, you may start to notice the aroma from the roaster will resemble that of toasted wheat or hay. It also serves to note that the drying stage is also taking place during this process, too.
During this stage, a Maillard Reaction takes place, which entails a chemical reaction—between amino acids and reducing sugars—that gives coffee beans a brown aesthetic. It is then when the roast begins to slow down, as the flavoring begins to take hold. Towards the end of this process, the coffee starts to ‘pop,’ which ignites the developmental stage.
3.) Developmental Stage
Home roasted decaf coffee beans by Sena Dreilinger via Flikr.
In the nascent portion of the developmental or ‘roasting’ stage, the reaction then switches to an exothermic one—which causes the bean’s shell to crack. The main reason for this is thanks to the preceding stages involving browning and drying. During these phases, the coffee bean slowly collects energy that in turn makes the coffee explode.
Overall, the roasting stage is characterized by when the aroma compounds are shifting and developing. It is extremely important the roaster treats this process with the utmost care, as one can easily make coffee that has a smoky smell and texture with flavoring that is too piercing for the average coffee drinker. Typically, the development stage takes up about 15-25% of the total roast time, according to the Barista Institute.
Thus concludes the basic roasting stages process. However, there are other ancillary factors, too, like roast degree and time that the roaster has to take into consideration.
The former part of this can be measured by either tasting or a color meter. Usually, you want to augment the coffee’s flavors prior to deciding the roast degree. Generally, light-roasted coffees prove to be more acidic, while dark roasted ones are more bitter. It’s also important to notice that it is much easier to distinguish between light roasted and dark roasted coffee, depending on what you want to roast.
Finally, you can also infer that expedient roasting is typically not a good idea, as it can lead to aforementioned consequences—i.e. a burnt roast—but it’s also indicative of an enhanced, flavorful experience.