The application process of freeze-drying machine in the Chinese herbal medicine industry integrates low-temperature biology and vacuum engineering, achieving efficient retention and quality improvement of active ingredients in medicinal materials through precise control of freezing, sublimation and other processes. The following are its core processes and technical points:

1、 Preprocessing stage

Cleaning and cutting

After screening, impurity removal, and cleaning, Chinese medicinal materials need to be sliced or segmented according to their characteristics. For example, American ginseng needs to be sliced evenly to facilitate subsequent freeze-drying.

Extraction liquid pretreatment (for liquid medicinal materials)

Traditional Chinese medicine decoctions or extracts need to be filtered, concentrated, clarified, and adjusted to a suitable density (such as a tray thickness of 8-15 millimeters) to prepare for freeze-drying.

2、 Freeze crystallization stage

Low temperature quick freezing

The material is rapidly cooled to below -40 ℃, forming tiny ice crystals inside the cells and reducing mechanical damage to the cell wall. For example, goji berries can maintain their original shape and color after freezing.

3、 Vacuum sublimation drying

One drying (sublimation stage)

In a vacuum environment (usually below 30Pa), sublimation latent heat is provided through radiation heating or conduction heating, causing ice crystals to vaporize directly into water vapor. During this stage, the temperature is controlled at -30 ℃~0 ℃ for about 18-30 hours, and most of the free water is removed.

Analysis drying (secondary drying)

Raise the temperature to 10 ℃~50 ℃ and remove the bound water. For example, honeysuckle requires precise temperature control at this stage to maintain a chlorogenic acid content of over 2.8%, far exceeding the pharmacopoeia standard of 35.

4、 Post processing and standardization

Low temperature crushing and packaging

The freeze-dried medicinal materials have a porous sponge like structure and need to be crushed into fine powder at low temperatures to avoid moisture absorption and clumping. For example, when a compound is freeze-dried and crushed into a powder, the effective ingredient dissolution rate is significantly increased by 23%.

Quality inspection and storage

Verify the freeze-drying effect through pressure rise testing to ensure a moisture content below 5%. The finished product can be stored at room temperature for 2-3 years without the need for preservatives and with stable microbial indicators.

In short, the application of freeze-drying machines runs through the entire chain of traditional Chinese medicine processing, demonstrating irreplaceable advantages from single herb processing to complex formulation production. In the future, with the upgrading of intelligence (such as AI freeze-drying curve prediction), its role in the modernization process of traditional Chinese medicine will become more prominent.