Roasting skills of coffee beans at home

Coffee roasting (coffee roasting) refers to the heating of raw beans to convert starch in raw beans into sugars and acids at high temperature, cellulose and other substances will be carbonized to varying degrees, water and carbon dioxide will be volatilized, protein will be converted into enzymes and fats, and the remaining substances will be combined to form an oil film on the surface of coffee beans, and in this process will produce sour, bitter, sweet and other flavors of coffee. The process by which raw beans are converted into dark brown beans by forming a mellow degree and hue. Because a variety of small changes in temperature, heat and other small changes in the baking process can change the taste of beans, different beans have different characteristics, and baking is a fast operation in a short time, so it is required to accurately budget the baking process and adjust it timely.

This kind of household roaster uses alcohol lamp or gas lamp as the heat source, while the larger one directly uses the flame on the gas stove as the heat source. The advantage of this kind of roaster is intuitive, easy to control the baking degree, easy to clean the silver skin, but the baking temperature is not easy to control.

Operation steps of manual semi-direct fire drum roaster:

1) put the raw coffee beans in the baking drum, the quantity of the raw beans depends on the size of the drum, and then seal the drum.

2) ignite the fire source, shake the handle at a uniform speed, and turn the baking drum to make the beans in the drum turn evenly.

3) after 3-4 minutes of baking, the beans in the jar began to turn yellow and the silver skin fell off, giving off a fragrance.

4) after baking for 6-7 minutes, the beans in the jar turned brown and began to give off white smoke, and began to explode in about 8 minutes.

5) about 10 minutes or so, the explosion ends. If you like the light taste, you can produce beans. Instead, continue to bake and wait for the second explosion.

6) in 12 minutes, the second explosion is completed, and the beans are produced quickly, cooled by an electric fan, and the baking is over.