What is a pilot freeze dryer?
The pilot freeze dryer is a device used for freeze-drying food and other substances. Freeze-drying is a process that involves freezing the material at low temperatures and removing the moisture under vacuum conditions, preserving the quality of the material and extending its shelf life.
Pilot freeze dryers are widely used in food processing, pharmaceuticals, biotechnology, and other fields to freeze-dry various food products, medications, and biological preparations, preserving their original flavor, nutrients, and activity.
Pilot Freeze Dryer Features
- Compact structure and small footprint.
- Utilize freezing and vacuum systems to rapidly lower the temperature of the material and remove the moisture through sublimation.
- Adjustable parameters for freezing and vacuum to accommodate the processing requirements of different substances.
- The equipment is usually made of stainless steel, making it easy to clean and maintain.
- Equipped with an automatic control system to monitor and regulate parameters such as temperature, pressure, and time throughout the freeze-drying process.
Freeze Drying Principle
The principle of freeze-drying, also known as cryodesiccation or vacuum drying, involves the removal of moisture from a substance by controlling temperature and pressure to facilitate sublimation.
The key objective of freeze-drying is the removal of moisture through sublimation without transitioning the substance into a liquid state. This helps preserve the structure and activity of the material, prolonging its stability and shelf life. Additionally, freeze-drying minimizes thermal and chemical damage to the material by operating under low-temperature and vacuum conditions.
Freeze-drying technology finds extensive applications in pharmaceuticals, food processing, biotechnology, and other industries for drying and preservation purposes. It allows for the drying and preservation of pharmaceuticals, vaccines, and food products without the need for heating, thereby avoiding degradation and preserving the activity and quality of heat-sensitive substances.
Freezing: The material to be processed is first frozen to a low temperature, typically below its freezing point. This causes the water within the material to form solid ice crystals, separating the water from the substance’s solution.
Primary Drying: Under frozen conditions, a vacuum is applied to induce direct sublimation of the ice crystals into a gas phase without transitioning into a liquid phase. This process is known as primary drying. The water evaporates from the material as a gas, facilitated by reducing the pressure, which lowers the boiling point of the water and promotes sublimation.
Secondary Drying: After the primary drying process, there may still be residual adsorbed or bound water present within the material. To further reduce the moisture content, the temperature is slightly increased to facilitate the evaporation of these residual water molecules. This process is referred to as secondary drying.