An impingement oven (40) includes an upper housing structure (46) forming the exterior of the upper half of the impingement oven and a lower housing structure (48) to mate with the upper housing structure. An interior impingement housing (62) is positioned interior to the upper and lower housing structures (46) and (48). A conveyor (60) extends through the interior impingement housing (62). The inside surfaces of the upper and lower housing structures (46) and (48) cooperate with the interior impingement housing (62) to define upright supply chambers (80a) and (80b) on opposite sides of the impingement oven to direct cooking medium downwardly upon the work products being carried by the conveyor and also upwardly through the porous belt of the conveyor, thereby to thermally process the work products being carried on the conveyor.

A thermal processing apparatus includes a conveyor belt for supporting work products during thermal processing that moves along a spiral path moving in a first direction arranged as a first tiered stack and then moves along a spiral path in a second direction arranged as a second tiered stack. A circulation system induces gaseous thermal processing medium from the tiers of the first and second spiral conveyor belt stacks and forces the thermal processing medium through a heat exchanger and then back to the tiers of the spiral conveyor belt stacks. The first tiered stack is divided into a first processing zone and a second processing zone, and the second tiered stack is divided into a third processing zone and fourth processing zone. A source of thermal processing medium is directed at the first processing zone to thermally treat the work product in the first zone by enhanced heat transfer. Optionally, a source of thermal processing medium is directed at the fourth processing zone to complete the thermally treatment the work product.

A particulate material freezing device includes a belt and an injection plate. The belt is configured to support conveyance of a particulate material and has air permeability. The injection plate includes a plurality of injection holes configured to inject a cooling gas to the belt from below. Further, the belt includes a sliding portion configured to move while sliding on an upper surface of the injection plate in a traveling direction of the belt. Thus, the particulate material freezing device is implemented where a flow of the cooling gas is stabilized.

A particles object freezing device includes an air-permeable belt configured to support conveyance of a particles object, and an injection plate which includes a plurality of injection holes configured to inject a cooling gas for fluidizing the particles object toward the belt from below. The injection plate includes a first injection part and a second injection part which are disposed along a width direction of the belt, and are different in opening ratio. A first boundary between the first injection part and the second injection part is along a traveling direction of the belt.

A food freezer includes: a first housing having a first chamber arranged internally within for providing a freezing gas to a food product within the first chamber; a second housing having a second chamber arranged internally within and being in fluid communication with the first chamber for exhausting the freezing gas from the first chamber; an adjustable opening disposed at a common wall between the first chamber and the second chamber for controlling a flow of the freezing gas moving from the first chamber to the second chamber, the adjustable opening disposed to provide a flow path for the flow of the freezing gas to a region of the second chamber for exhaust from said second chamber to an area external to the first housing and second housing; and a pressure curtain comprising the exhaust and disposed at the second chamber to prevent atmosphere from the area external to the first housing and second housing from entering said housings. A related method of exhausting freezing gas is also provided.

Disclosed are methodology and apparatus for freezing the exterior crust of products, such as food products, in a manner that does not cause the exterior of the product to adhere to the surface on which it is placed during or after the freezing.

Disclosed are methodology and apparatus for freezing the exterior crust of products, such as food products, in a manner that does not cause the exterior of the product to adhere to the surface on which it is placed during or after the freezing.

A variable bi-directional airflow thermal processing system may include a thermal processing medium supply for substantially horizontally supplying thermal processing medium to the thermal processing chamber at a target temperature and velocity and a thermal processing medium directing assembly configured to divide the spiral stack into at least one treatment zone and at least one return zone both extending along a height of the spiral stack and substantially confined within a footprint of the spiral stack, wherein the thermal processing medium supply substantially horizontally supplies thermal processing medium to the at least one treatment zone and substantially horizontally withdraws thermal processing medium from the at least one return zone.