Freeze-drying, sublimation, the cake, and why dry material changes slowly.
Freeze-drying removes frozen water by sublimation and leaves a dry cake that is easier to hold during ordinary transit than a liquid preparation. A dry material changes slowly when sealed, protected from moisture, and kept within the product’s handling guidance.
The cake can crack, shrink, or look different after transport without that appearance alone proving a problem. Record the condition on arrival and use the storage notes supplied for the material.