Today’s home freeze dryers make freeze-drying very simple. The way that it works can be summed up in the below steps:
Select the food items, place them on the tray/sheet, slide the trays into the freeze dryer, and press start.
I like to freeze foods on the tray in my freezer before placing them in the freeze dryer to make the freeze-drying process more efficient, however, it is not required to do so.
Freezing phase: the freeze dryer freezes the food to between -30 degrees and -50 degrees Fahrenheit.
Vacuum Pump: Once frozen, the vacuum pump automatically turns on and creates a powerful vacuum around the food.
Drying (sublimation) Phase: The trays gradually warm while the food is still frozen causing a process called sublimation to occur which removes water from the food and allows it to keep its original shape, flavor, and nutrition