The key to temperature control in coffee bean roasting

The effect of roasting temperature on coffee beans

The roasting process of coffee is to heat the raw beans to a certain temperature to make them undergo chemical changes, thus producing a special aroma and flavor. In the entire roasting process, temperature control is very important. This article will discuss the key points of temperature control in coffee bean roasting.

Initial heating stage

Before starting to heat the coffee beans, you need to preheat the equipment to the appropriate temperature. This stage is called the initial heating stage. Generally speaking, a lower temperature (about 180-200°C) is used during the initial heating to avoid rising too quickly and causing uneven color changes on the outer layer.

Water loss and acid generation

As time goes by and the temperature rises, water loss will occur inside the coffee beans. This process is called "dry-wet conversion". At the same time, a large amount of acidic substances are formed in the boundary layer and aroma begins to be produced. Temperature control at this stage is very important and is generally carried out between 200-220°C.

Reaction of carbohydrates and proteins

When the temperature of coffee beans reaches about 220°C, sugars and proteins begin to react. This stage is called "caramelization". During this process, the surface of the coffee beans will appear burnt black and bitter substances will be produced. Therefore, when controlling the roasting temperature, you need to be careful to avoid too high a temperature that will cause excessive bitterness.

Uniform heating inside and outside

In order to ensure that the inside and outside of the coffee beans are heated evenly, the heating time and intensity need to be adjusted appropriately. If you only focus on the appearance color and ignore the internal state, it may lead to a poor taste; on the contrary, if you only pursue internal perfection and ignore the appearance, it will affect the visual effect of the coffee.

Stop heating and cooling

When the desired aroma and flavor are achieved, heating needs to be stopped and cooling needs to be performed in time. Otherwise, chemical reactions will continue to occur under the residual temperature, causing changes in the flavor of the coffee. The cooling process generally uses natural cooling or rapid cooling.

Summarize

Roasting temperature is one of the key factors affecting the flavor and aroma of coffee beans. By properly controlling the roasting temperature, coffee beans can achieve the best quality. Using the right temperature at different stages can achieve important steps such as water loss, acid production, sugar and protein reaction, and ensure uniform heating inside and outside, as well as timely termination of heating and cooling.

Only by deeply understanding and mastering these key points can we achieve better results in the roasting process of coffee beans and provide consumers with a more delicious coffee experience.