Mechanical Freezers uses the Indirect cooling system which utilizes the properties of refrigerated airs such as Ammonia, Freons, and for some cases Close Compound CO2 or Carbon Dioxide which runs on -20°C to -50°C. The amount of time it takes to freeze a food in Mechanical freezers took about an average time of 142 seconds
Mechanical Freezers function by circulating a refrigerant, normally ammonia, around the system, which withdraws heat from the food product. This heat is then transferred to a condenser and dissipated into air or water. The refrigerant itself, now a high pressure, hot liquid, is directed into an evaporator. As it passes through an expansion valve, it is cooled and then vaporizes into a gaseous state. Now a low pressure, low temperature gas again, it can be reintroduced into the system.
Mechanical systems have a higher capital outlay, but can provide financial benefits in the longer term.