Coffee Bean Roasting: The Secret of the Pop

The coffee bean roasting process is that the cafe treats the raw beans with high temperature to produce a special aroma and flavor. In this process, the crackling sound becomes one of the important indicators that roasters pay attention to.

Coffee beans explode twice during the roasting process. The first explosion is called the "first bloom," which occurs when the water inside the coffee bean evaporates and creates pressure. When the water reaches a critical point, it quickly turns into steam and rushes out of the bean at a very high speed, causing the clear peeling sound.

The second burst is called the "second bloom", which occurs when the coffee beans begin to change color. At this time, due to the rise in internal temperature, the oil begins to release, and the residual water continues to convert into steam, huge pressure is formed at extremely high temperature and released quickly. This phenomenon is usually accompanied by a louder and louder sound and a strong aroma.

These two bursts are very important in determining whether the coffee has reached the ideal roasting degree. The sound and time of the first blossom are usually used to judge the moisture content of the coffee beans, while the second blossom is a key indicator for roasters to determine whether the coffee beans have achieved the desired flavor.

The crackling sound is not just an indicator, it can also provide more information to the roaster. By observing the frequency, intensity and duration of the crackling sound, the roaster can understand the changes in the temperature inside the coffee beans and adjust the parameters of the roasting process based on this information to achieve the best results.

In short, the explosion of coffee beans during roasting is caused by the release of pressure due to the evaporation of internal water. These two explosions not only provide an important basis for determining moisture content and flavor, but also provide valuable reference for roasters to adjust parameters. Therefore, when roasting coffee beans, we need to pay enough attention to the explosion sound and its mystery.