my country is the world's largest producer, processor, and exporter of Chinese herbal medicines. There are numerous varieties of Chinese herbal medicines, each with unique properties, processing techniques, and standards. For dehydrating and drying these herbs, it's crucial to choose the right dryer and drying process to ensure the quality, appearance, and efficacy of the finished product. Below is a summary of three key points in drying Chinese herbal medicines.

Key Point 1: Selecting a Drying Process Based on the Characteristics of the Herbal Medicine

1. Chinese herbal medicines vary greatly in appearance, quality, size, coarseness, medicinal properties, moisture content, and processing steps. Therefore, appropriate drying parameters such as temperature, humidity, and time must be selected based on their characteristics.

2. Viscous Chinese herbal medicines contain abundant viscous sugars and tend to become sticky after slicing, so they are best dried at medium to high temperatures.

3. The volatile oils in oily Chinese herbal medicines are extremely temperature-sensitive. Excessively high temperatures can cause the oil to overflow and deteriorate. Therefore, drying at a medium-low temperature is recommended to prevent oil release and darkening, thereby better preserving the active ingredients.

4. Color: The color and appearance of dried Chinese medicinal materials are crucial to their quality. Therefore, avoid using excessively high drying temperatures. Care should be taken to gradually increase the temperature from a medium-low temperature to a low temperature.
Key Point 2: Controlling Drying Temperature and Humidity

The drying temperature directly determines the degree to which the key components of a Chinese herbal medicine are preserved during the drying process. Temperatures that are too high or too low can negatively impact the quality of the medicinal material. Therefore, selecting an appropriate drying temperature based on the characteristics of the individual Chinese medicinal material can positively impact the preservation of its medicinal properties, appearance, and subsequent storage.

Humidity control directly affects the shape and color of dried Chinese medicinal materials, and even determines their quality. Therefore, it is crucial to properly balance the relationship between temperature and humidity during the drying process.

Key Point 3: Controlling the Humidity of the Herbal Material

Each medicinal material has a different initial moisture content, so the amount of moisture removed during the drying process also has requirements. For example, when drying goji berries, the moisture content of fresh fruit is as high as 80%. However, during the initial heating phase, moisture removal is not permitted. However, in the second phase, at 45°C, significant moisture removal is required. The moisture removal is then slightly reduced until uniform moisture removal is achieved. This process, spanning approximately 25 hours across four phases with varying temperature and humidity settings, yields a complete batch of high-quality goji berries, achieving a high drying throughput and energy conservation.
Understanding and mastering the three key points of Chinese medicinal material drying and selecting appropriate drying equipment can effectively improve dehydration capacity and drying quality, reduce drying costs, and increase profit margins. Of course, drying is a complex process, and changes in any objective factor can affect the energy consumption and cost of the entire drying process. Only through diligent observation, analysis, and optimization can we achieve optimal drying results with less effort.