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The Freeze Drying Process
The freeze drying process is very slow. It is dried in a frozen state hence the name “freeze dried”. Moisture (ice crystals) are removed as a gas, similar to evaporation. This process is technically called sublimation. The specimens are put into the upper chamber of the freeze dryer. Here the temperature is brought down to approximately minus twenty degrees. Then the ice bank below is brought down to approximately minus sixty degrees. Then the vacuum pump is cut on where it brings the pressure almost down to zero allowing for evaporation. The temperature of the upper chamber is gradually raised over a period of time. Because this is being done in the frozen state the frozen cells do not collapse and the muscle itself does not shrink or collapse. The cellular structure hardens to what could be compared to balsa wood. All specimens are injected and washed with a preservative and bug/moth deterrent is applied after drying. The average time to dry horns is probably about six weeks. Drying times will vary depending on mass and size of specimen.
There is so much that can be freeze dried, from the smallest most fragile to much larger specimens. Although on the larger specimens typically the animal is skinned and a carved body is inserted where the head and legs are left alone to freeze dry. Wires are inserted when needed for dioramas. For best results keep clean and apply bug retardant annually.