Techniques for evenly heating coffee beans in a commercial roaster
Uniform heating of coffee beans in commercial roasters is the key to ensuring roasting quality. Here are some practical tips:
Control the rotational speed of the baking machine reasonably
Rotational speed and stirring effect: The rotational speed of the roaster directly affects the frequency at which coffee beans are stirred inside the drum. If the rotational speed is too low, coffee beans may accumulate at the bottom of the drum, resulting in uneven heating. If the rotational speed is too high, the coffee beans may tumble excessively, increasing the production of debris and even causing some parts of the beans to be over-roasted on the surface.
Adjustment suggestion: According to the model of the roaster and the variety and quantity of coffee beans, adjust the rotational speed to an appropriate range. Generally, at the beginning of roasting, the rotational speed can be appropriately increased to promote uniform heating of the coffee beans. In the later stage of baking, the speed can be appropriately reduced to avoid excessive stirring.
Optimize the damper and airflow of the baking machine
The function of the air door: The air door controls the size and direction of the airflow inside the roaster and has a significant impact on the uniformity of heating of coffee beans. Appropriate air flow can carry away the smoke and impurities produced during the roasting process, and at the same time promote uniform heating of coffee beans.
Adjust the strategy: At the beginning of roasting, you can appropriately open the air door to increase the airflow and help the coffee beans dehydrate quickly. During the middle stage of roasting, adjust the size of the air damper in a timely manner according to the state of the coffee beans and the roasting requirements. In the later stage of roasting, the air door can be appropriately reduced to prevent the coffee beans from losing too much water due to excessive air flow or overroasting on the surface.
Precisely control the baking temperature and time
Temperature and heating uniformity: Roasting temperature is one of the key factors affecting the heating uniformity of coffee beans. Both excessively high and low temperatures can cause coffee beans to be heated unevenly.
Time management: The length of roasting time also directly affects the uniformity of heating of coffee beans. If the time is too short, the coffee beans may not be fully roasted. If the time is too long, it may lead to over-roasting of coffee beans.
Operation suggestion: Set the appropriate roasting temperature and time based on the variety, origin and roasting requirements of the coffee beans. During the roasting process, closely monitor the changes in the color and aroma of the coffee beans, and adjust the temperature and time in a timely manner to ensure that the coffee beans are heated evenly.
Reasonably control the amount of coffee beans added
Dosage and heating: Excessive or insufficient dosage of coffee beans may affect the uniformity of their heating in the roaster. Excessive input may lead to the accumulation of coffee beans and uneven heating. If the amount added is too small, it may lead to uneven heat distribution inside the baking machine, which will also affect the heating effect.
Suggested dosage: According to the capacity of the roaster and the variety and size of the coffee beans, the dosage should be reasonably controlled. Generally, the amount of input should account for 70% to 80% of the capacity of the baking machine.
Regularly maintain and clean the baking machine
The importance of maintenance and cleaning: During the operation of the roaster, impurities such as coffee bean debris and oil will accumulate. These impurities may affect the heat conduction efficiency of the roaster and, in turn, the uniformity of heating of the coffee beans.
Maintenance suggestion: Regularly clean the debris and grease inside the baking machine to keep it clean. At the same time, check whether the heating elements, air doors and other components of the baking machine are working properly to ensure the stable performance of the baking machine.
Adopt a batch roasting or mixed roasting strategy
Batch roasting: For roasting a large quantity of coffee beans, it is advisable to do it in batches to ensure that each batch of coffee beans is evenly heated in the roaster.
Mixed roasting: For coffee beans of different varieties or origins, you can try mixed roasting. By adjusting the roasting parameters, different coffee beans can complement each other during the roasting process, achieving a better heating effect. However, it should be noted that for mixed roasting, a thorough understanding of the characteristics of coffee beans is required, and multiple experiments must be conducted to find the best roasting solution.