中药浸膏真空干燥过程中表面结壳行为的成因、影响因素与研究策略

Discussion of causes, influencing factors and research strategies of surface crusting behavior of traditional Chinese medicine extracts during vacuum drying

真空干燥是中药浸膏的主要干燥方式之一,但效率低下、干膏质量不佳,已成为中药制药行业的痛点、难点问题。表面结壳是引起该问题的重要原因,但相关研究尚属空白,实践中面对该问题束手无策。首先阐述了表面结壳的成因、探讨了表面结壳行为影响因素;然后分析了利用质构仪技术建立其表征方法体系的可行性;再基于中药浸膏干燥特性以及多种干燥技术,分析中药浸膏真空干燥过程中表面结壳行为是表面无结壳、表面壳层固化与表面壳层增厚3阶段演变过程;最后根据多种其他干燥技术原理与特点,针对各阶段进行精准调控,推迟表面结壳、延缓壳层固化、优化壳层结构,将有助于提高中药浸膏真空干燥效率,保证干膏质量。

Vacuum drying is one of the main drying methods of traditional Chinese medicine extracts, but the low efficiency and poor quality of dry extract have become the pain point and difficult problem of traditional Chinese medicine pharmaceutical industry. The surface crust is an important cause of this problem, but there is no relevant research report and no effective way to solve it in practice.In this paper, the causes of surface crusting and the influencing factors of surface crusting behavior are discussed. Then the feasibility of establishing the characterization method system by using the texture analyzer technology was analyzed. Based on the drying characteristics of traditional Chinese medicine extracts and various drying technologies, the surface crusting behavior of traditional Chinese medicine extract during vacuum drying process was analyzed as a three-stage sequential evolution process of no crusting on the surface, surface shell solidification and surface shell thickening. Finally, according to the principles and characteristics of various other drying technologies, accurate control of each stage, delaying surface crusting, delaying shell solidification and optimizing shell structure will help to improve vacuum drying efficiency of traditional Chinese medicine extracts and ensure the quality of dry paste.