Opening During Operation; How Do I Know If My Food Is Dry - Harvest Right Home Freeze Dryer Owner's Manual

reduce the freeze time in the freeze
dryer by approximately 1 hour – 1.5
hours. Food that is pre-frozen should
go into a cold chamber; Run the
freeze cycle for 30 minutes before
taking food out of the freezer and
putting it in the freeze dryer.
5.5 OPENING THE FREEZE DRYER
DURING OPERATION
There are three main processes that
occur during freeze drying:
1.
The food is frozen to very low
temperatures.
2.
Under vacuum pressure the
oxygen in the chamber is removed
(no oxidation of the food occurs)
and the ice sublimates at low
temperatures (about 7 degrees
Fahrenheit).
3.
A small amount of heat in the
vacuum chamber begins the
sublimation process and removes
the moisture from the food. The
moisture condenses on the inside,
cooled walls of the vacuum chamber.
It is okay to open the freeze dryer
chamber while it is in the freezing
stage of the freeze dry process, but
it is discouraged as extremely low
temperatures may damage your skin
and it renders useless the freezing
part of the cycle (the food may not
achieve a very low temperature if the
door is left open).
Opening the chamber during the
vacuum process (processes 2 and 3

listed above) is impossible because
the vacuum tightly seals the door to
the freeze dry machine. In order to
open the door, turn off the vacuum
pump and open the drain valve to
vent the vacuum chamber. Opening
the chamber door during these
stages interrupts the freeze dry
process because sublimation cannot
take place unless the chamber is
vacuum-sealed. The result may be a
less than ideal freeze-dried product.

5.6 HOW DO I KNOW IF MY FOOD IS DRY?

Your freeze dryer will sense the
moisture in the food and finish when
it has sensed that all of the moisture
is removed. While your freeze dryer
is very accurate, it is a good practice
to find one or two of the thickest
pieces of food and either break them
in half or taste them. If there is any
moisture left in the food, it will be
in the center. You will immediately
feel or taste moisture which usually
manifests itself as cold and wet.
If this happens, simply click the
option to "Add More Dry Time" and
your freeze dryer will add a couple of
hours to finish the product.
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