Looking at the current research on the drying of Chinese herbal medicines and traditional Chinese medicine decoction pieces, the following problems still exist:
1. The theory of drying theory is not deep. There are few explanations and quantitative analysis of the many complex changes that occur during the drying process of Chinese herbal medicines and the causes and extents of degradation of active ingredients with drying time, and lack of corresponding simulation software.
2. Less special drying equipment. In recent years, although the development and quality of traditional Chinese medicine drying equipment have improved, but overall, the drying of Chinese herbal medicines is basically in the state of borrowing other materials drying equipment, few special equipments, and no serialization and standardization.
3. Less systematic research. At present, most of the drying process research is limited to the comparison of working methods or the comparison of drying time and energy consumption. There are few reports on the systematic study of the mass transfer mechanism, the effective component change mechanism, the drying process parameters optimization, and the drying equipment design. This means that there are few studies on the drying technology of relatively complete varieties of Chinese herbal medicines.
The drying process of Chinese herbal medicines and decoction pieces is actually a process of dynamic change of water, heat and active ingredients. The three interact and restrict each other, and then reach a relative equilibrium state. In the study, not only the factors affecting the three factors in the drying process, such as drying temperature, time, space scale, ambient temperature, humidity, gas flow velocity, surface morphology, etc., but also the influence of these factors should be investigated. Dynamic change process and mutual constraint relationship, and with the help of a large number of experimental data, design and development of computer software, simulation of the comprehensive impact of different factors, thus establishing a variety of Chinese herbal medicine pieces drying model. Through the establishment and prediction of the model, various influence factors are adjusted to find the optimal combination, so that the water, heat and active ingredients can achieve the best balance state and drying effect.
Chinese herbal medicine drying equipment, at present, the water content of Chinese herbal medicines and decoction pieces after drying is required to be 8%~12%. The author believes that this standard is too general and does not take into account the differences between Chinese herbal medicines and decoction pieces. It is well known that the types of chemical components contained in different pieces, the types of microorganisms that may be contained, the sites of medicinal materials and their structures may vary, so the effectiveness, safety and stability of the tablets are not affected by the degree of moisture. If you use a unified standard to ask for it, it seems biased. This requires researchers to conduct research on the correlation between water, chemical composition and curative effect. Through systematic and in-depth research, it reveals and predicts the influence of dryness on all aspects of decoction pieces, and formulates various reasonable and standardized Chinese herbal medicine pieces. The water content standard, thereby improving the quality of the medicinal materials.
In addition, according to the characteristics and classification of Chinese herbal medicines and decoction pieces, and in combination with mechanical design, computer control and other disciplines, the parameters parameters necessary for the drying process should be formulated, and the development of Chinese herbal medicines and decoction pieces can be applied to large-scale production. And drying equipment for decoction pieces that are easy to popularize.