Vacuum freeze drying
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Industrial Production Plants with Daily Throughputs Ranging from 500 kg to 60 tons of Fresh Product per Unit

Industrial Freeze-Drying FREEZE DRYING Freeze-drying is used to preserve products The main application for freeze-drying results containing water or solvents. Good preser- from the remarkable advantages of the final vation of fragrances, flavorings and ingre- product with respect to the conservation of dients with nutritional value is crucial in the volatile aromatics, heat-sensitive ingredients, foodstuff industry. With proper packaging color, taste, original shape, texture and nu- and storage, freeze-dried products can be tritional value, as well as quick rehydration stored for a very...

FREEZE DRYING The Principles of Freeze-Drying At atmospheric pressure (approx. 1,000 mbar) water can have three physical states I Solid; I Liquid; I Gaseous. Below the triple-point (for pure water: 6.1 mbar at 0°C), only the solid and the gaseous states exist. The principle of freeze/sublimation-drying is based on this physical fact. The ice in the product is directly converted into water vapor (without passing through the “fluid state”) if the ambient partial water vapor pressure is lower than the partial pressure of the ice at its relevant temperature. The freeze-drying process is divided...

FREEZE DRYING For freezing of liquids, especially coffee zones. The entry and exit operation is rea- extract, automatic freezing belts are used. lized by vacuum lock systems enabling the Different temperature zones, variable veloc- continuous operation of freeze-drying. ity of the belt and adjustable thickness of the product layer permit optimized freezing In addition to the known freeze-drying conditions adapted to the requirements of method with trays (static freeze-drying) ALD offers so-called “Dynamic Freeze-Drying Installations”. This drying method is used for fluid/free-flowing...

FREEZE DRYING a very short drying time and thereby an Condenser Vacuum System excellent quality of the dried product (flavor retention) is attainable. The most efficient water vapour pump is a surface at low temperature, if the tempera- The necessary heat for the sublimation of ture is lower than the freezing temperature water is conveyed through direct contact corresponding to the particular pressure. between the synthetic belts and the heating The size of the condenser surface and the plates mounted below. Different adjustable area of the connecting tube to the sublima- temperature zones...

FREEZE DRYING Refrigeration Plant In industrial freeze-drying installations, great refrigeration capacities must be achieved at low evaporation temperatures of less than minus 40 °C down to minus 60 °C. Ammonia absorption installations and compressor-type installations may be used for the generation of the necessary refrigeration capacity. The final/adequate choice of the refrigeration system depends on various factors such as cost of electrical energy and heavy oil, process, operation and product parameters. Vacuum pump system of a continuous freezedrying plant Processing Lines ALD Vacuum...