Coffee bean roasting: eight stages from green beans to aromatic coffee
Coffee roasting is the process of putting raw beans through a series of heating and processing steps to transform them into the aromatic coffee we love. This process can be divided into eight main stages, each of which has an important impact on the final taste.
1. Peel and shell
First, the freshly picked ripe coffee cherries are peeled and shelled. This step is usually done using mechanical equipment to ensure high efficiency and quality.
2. Fermentation
During the fermentation phase, the peeled coffee seeds are placed in contact with the pulp and fermented at a specific temperature. This step helps to remove the pulp remaining on the seeds and changes the internal chemical composition of the seeds through microbial action.
3. Washing
Washing is to rinse the fermented coffee seeds with water to remove residual substances. It also helps to remove the bad taste produced during the fermentation process and make the coffee beans purer.
4. Dry in the shade
After washing, the coffee seeds are spread out on large platforms to dry in the shade. This process takes a while, usually from a few days to a few weeks. Shade drying helps reduce the moisture content of the seeds and prepares them for subsequent roasting.
5. Pre-baking treatment
Before roasting, the coffee beans may go through additional processing steps, such as removing residues, screening out unacceptable beans, or undergoing special treatments to change the taste and flavor.
6. Baking
Roasting is one of the most critical and challenging steps in the entire process. By heating the coffee beans to high temperatures, a complex reaction occurs in their internal chemical components, producing the aroma and flavor we love.
7. Cooling
After roasting, the coffee beans need to be cooled quickly to stop the internal reactions. This can be done by placing the beans in a cooling device, or using natural fans.
8. Storage and grinding
Finally, the roasted and cooled coffee beans need to be properly stored to maintain their freshness. Once ready to drink, the beans are ground into a powder and used to make the rich, aromatic coffee we all love.
In summary, the eight stages from green beans to aroma include peeling, fermentation, washing, shade drying, pre-roasting, roasting, cooling, and final storage and grinding. Each stage has an important impact on the final taste, and perfect mastery of these steps is a skill that must be possessed by a good barista.