For
the purpose of preservation of the processed food
for a long period, it is most important to make
the freezing and cooling as quickly as possible
so as to resist microorganism, enzyme and chemical
reaction. Therefore, after processing, the products
should be cooled and frozen promptly.
And also the cooling and freezing time itself
should be minimum in order to restrict the crystallization
effect of ice.
Through the expansion valve, that reduces the
pressure in the pipe, the refrigerant is led
back to the evaporator. In this way, the process
starts all over again.