Freeze Drying

Freeze-drying gently removes moisture from temperature- and structure-sensitive products, such as food, biotechnological preparations, or vaccines. The physical principle of sublimation describes the direct transition from ice to water vapor, bypassing the liquid phase. The frozen product is dried in a precisely controlled vacuum environment without thawing. This process preserves the product’s structure, extends shelf life, and offers a wide range of industrial and pharmaceutical applications.

Requirements

Freeze-drying imposes the highest requirements on the vacuum measurement devices used, as both product protection and process efficiency directly depend on precise pressure management. To avoid costly production downtimes, the devices must consistently provide reliable and reproducible readings throughout long drying cycles. Accurate pressure monitoring is particularly critical during the primary drying phase for the successful sublimation process. Equally essential is integrated temperature compensation to effectively eliminate distorted measurements caused by temperature fluctuations.

Suitable Products

VCP: The Pirani sensor of the VCP is equipped with a coiled platinum-rhodium filament, making it ideally suited for demanding applications – even in contact with aggressive media – within the measurement range of 1000 to 5e-4 mbar. The smooth surface of the filament material minimizes the deposition of oil vapors and other contaminants, which practically results in a significantly extended lifespan. This is confirmed by field tests under particularly critical operating conditions. The sensor reliably withstands steam sterilizations. The metal-sealed measurement cell and stainless-steel flange further contribute to the high robustness and durability of the transducer.

By using the VCP, process safety is improved while simultaneously reducing maintenance costs.

One of the world´s leading companies in the field of development and production of freeze dryers has trusted in the quality and precision of our vacuum sensors for many years.