Freeze-drying of emulsified systems: A review - ScienceDirect
Apr 30, 2016 A typical freeze-drying cycle consists of three stages: freezing, primary drying and secondary drying (Tang and Pikal, 2004).Fig. 2 gives an example of a recorder output trace from a freeze-drying cycle showing all these steps. In the first step the liquid is cooled, and as it freezes the solids become more concentrated in the remaining liquid.
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