The principle of a freeze dryer is a technical method of preliminarily freezing an aqueous article and then sublimating its water under vacuum to obtain a dried article. The freeze-dried articles are easy to store for a long time, and can be restored to the state before lyophilization and retain the original biochemical characteristics after adding water.
Vacuum freeze-drying technology is a high-tech dehydration technology that protects color, keeps freshness and maintains quality. In recent years, the consumption of freeze-dried food in Europe, America and Japan has increased rapidly, and for a long time, China's agricultural and livestock products have been exporting. The raw material or primary processing stage gives a general feeling of low technical content. By developing freeze-dried vegetables and meat, it will improve the grade of China's export food and obtain higher added value.
Pilot freeze dryer is common in daily life. Air freeze-drying technology, referred to as freeze-drying, is also known as sublimation air-drying. Freeze-drying is a specific method of pre-freezing water-containing materials and then subliming them in a vacuum state to obtain air-dried objects. Freeze-dried objects have basically unchanged original biological and chemical properties, and are easy to store for a long time. After soaking in water, it can be restored to the form before freeze-drying, and its original biochemical properties can be maintained. Therefore, freeze-drying technology is widely used in various fields such as industrial chemistry and medical equipment.