Coffee bean roasting: from light roast to dark roast, how much do you know?

Coffee bean roasting is the process of heating the raw coffee beans to cause chemical changes inside them, thereby changing their flavor and aroma. Depending on the roasting time and temperature, it can be divided into three levels: light roasting, medium roasting and dark roasting.

Light roasting means roasting coffee beans at a lower temperature for a shorter time. This degree of roasting usually retains the original sourness and floral and fruity aroma of the coffee beans, and produces some slight sweetness. Since there is still a certain proportion of tannins that have not been completely converted into soluble substances (such as glucose) inside the coffee beans during light roasting, the taste is relatively refreshing and has a certain astringency. This degree is suitable for people who like a bright and fresh taste and want to taste special flavor details.

Medium or City/American roast is also widely accepted. Medium roast means that you stop roasting when you see a small white or yellow spot appear in front of your eyes. This spot is the release of moisture and also a sign of carbon dioxide release. The roast level is between medium and dark roast.

Dark roasting is roasting coffee beans at a higher temperature for a longer time. This degree will produce more soluble substances inside the coffee beans, such as glucose and oil, making the taste richer and fuller, with a certain bitterness and caramel aroma. When dark roasting, tannins are basically completely converted into soluble substances, so the taste is relatively smooth and there is no astringency. This degree is suitable for people who like rich, bittersweet and heavy taste.

In short, when choosing coffee beans, you need to decide whether to roast lightly, medium or darkly according to your personal preference. Each degree has its own special flavor and aroma, and different levels of details and changes can be found during the tasting process.