Roasting process of coffee beans and matters needing attention

Among the many factors affecting the taste and flavor of coffee, roasting is the most important link. And baking itself is both a science and an art.

During the roasting process of 8-20 minutes, raw coffee beans (Green coffee been) produce a series of complex changes: from the appearance, the coffee beans gradually change from light green to light yellow, light brown, brown, dark brown, and if they are roasted very deeply (such as the roasting habit of southern Italy), they eventually become a dark brown on the surface; in terms of chemical changes, those in coffee beans. To put it simply, it is customary to divide coffee beans with different roasting levels into several different names: City,Full CIty,Espresso,French, etc.

The control of the roasting process of coffee beans is actually a process of removing or covering up the original bad taste of coffee beans in order to give full play to the original flavor of coffee. As for the fact that many coffee lovers are keen to prepare their own "mixed beans", the purpose is to let coffee from different places and varieties give full play to their own advantages and finally get the best taste (to be exact, it should be "the most suitable for your own taste").

The complete roasting process of coffee includes three stages: "dehydration", "first explosion" and "second explosion". Each stage represents the different changes of coffee beans under high temperature. Of course, according to your own needs, you can also decide to end baking at any time.

In the "dehydration" stage, the water in the raw coffee beans will be fully evaporated, and then the coffee will burst, that is, into the "explosion".

In the "explosion" stage, the starch in coffee beans will be saccharified at high temperature, and the unique "caramel flavor" felt when drinking coffee is determined by the control of this stage. some coffee beans that are shallow roasted, medium-roasted and medium-deep roasted will be roasted successively.

Then there will be a "second explosion", in which most people choose to end baking in order to achieve the best "caramel taste" and a lower degree of "sour taste" in the early stages of this stage (that is, within tens of seconds of the second burst of coffee beans), which is usually used to make Espresso. But if you choose to continue roasting, the acidity in the beans will disappear completely, and the sugars converted from the previous stage will be further carbonized, resulting in the loss of sour taste, reduced sweetness, and more and more bitterness of the coffee, so that the roasted beans, in addition to people in southern Italy can be made into Espresso and drink directly, coffee shops elsewhere are usually used as the base of fancy coffee.

After baking, the coffee beans need to be cooled quickly to avoid excessive "self-roasting". After that, after a day of proper preservation, the coffee beans will give full play to their best flavor.

It should be reminded that coffee beans of different varieties and different producing areas have their own "best roasting degree" according to their characteristics. Some responsible coffee bean suppliers will tell buyers the "recommended roasting degree" and "coffee flavor characteristics" of these beans. To prevent some of the original qualities of high-quality coffee beans from being undermined by improper roasting practices (for example, Costa Rican coffee beans are famous for their rich, bright sour taste, but overroasting can destroy these traits). Of course, for coffee enthusiasts, constantly experimenting and innovating is also a rare pleasure.