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FREEZING
Freezing is the processes in which all the liquids are changed into solids

This prevents the water loss

Prevents bacterial action
CONVENTIONAL SYSTEM
The meat is cooled to 4⁰C by usual refrigeration

Cutting and other operations increases the temperature

This have to be then cooled

Conventionally normal refrigeration is used but is inefficient and can produce localized cooling
CRYOGENIC FREEZING
The food enters the freezer through a conveyor belt tunnel
The liquid cryogen is sprayed at the exit which moves in the opposite direction
This tend the processes into a reversible system
The liquid cryogen evaporates
This then sucked in by means of an induction fan


The system is controlled by complex electronic circuit
Sensors senses the temperatures
Compares it with the pre fed values in the computer
Adjust the cryogen flow by means of adjusting the metering valve
Apart from the electronics the cryogenic instrumentation is used for the tank and the cryogen handling components

The cooling chamber must be free from air
Vacuum not necessary
Presence of air reduces the efficiency of recycling of the cryogen
It also increases the temperature of the chamber increasing the cryogen consumption
MOBILE FREEZING UNIT
This is suitable where its difficult to setup a freezing unit
It can be attached to trucks or setup in containers
Contains a partitioned cryogenic storage tank
The load is stationary
The cryogen is sprayed on to the load
No recovery of cryogen is possible
CRYONICS
Preserving organs and even human bodies
Preserved for future use, scientific analysis, resurrection
The liquid content should not crystallize as in freezing
Cryoprotectants are used which forms non freezing solutions with the liquid content
Dimethyl sulfoxide (DMOS)
The processes is slow allowing equilibrium of the chemicals

REFERENCE
CRYOGENICS FREEZING APPARATUS AND METHODS PATENT NO:5 186 008
COOLING APPARATUS FOR CRYONIC COOLING PATENT NO:US 2006/0283196
TRANSPORT COOLING PATENT NO: US6 408640 B1