One economic food freezing method is put them into a blast freezer room, which is ultra-low temperature. A blast freezer also plays the role of cold storage, products can be well preserved under -18C.
Typically, blast freezers consist of 3 parts: Compressor system, condenser fans and wall panels. The blast air is created and circulated by condenser fans which will continue working until the room temperature reach desired, chilled air impact products and quick cool them down.
Blast freezer is very similar with cold room whatever the design and structure, the main difference is blast freezer can quite pull temperature down to desired, very high performance.