he drying chamber of a freeze drying machine has to be vacuum tight. To freeze dry an object or solution it first has to be frozen so the water separates off from the other material as ice crystals. A vacuum is then created in the drying chamber that radically lowers the boiling point of the frozen water. Heat going into the frozen product while under vacuum promotes a process known as sublimation in which the ice comes away as vapour rather than melting. This leaves all the other material such as minerals, nutrients, volatiles etc. intact and eventually dry.
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Freeze Driers - Frozen in Time
Frozen In Time Ltd is your No 1 manufacturer of Freeze Driers and Vacuum Cold Traps. Find out more at http://www.scoot.co.uk/CWVJ584