Tunnel freezer and method for freezing a layer of foodstuffs

A method for freezing foodstuffs that are arranged in a layer, the foodstuffs having a determined supercooled temperature range in which water in the foodstuffs is supercooled, the method comprising:

• conveying, using a conveyor unit, the layer of the foodstuffs through each of a plurality of housing sections comprised in a housing;
• in each housing section, of the plurality of housing sections, providing a stream of a gaseous medium and cooling the gaseous medium in the stream;
• forcing, in a first housing section of the plurality of housing sections, the stream of the gaseous medium to flow in a first direction through the layer of the foodstuffs, and cooling, in the first housing section, the layer of the foodstuffs until an average temperature of the foodstuffs is in the supercooled temperature range;
• conveying, using the conveyor unit and when the average temperature of the foodstuffs is in the supercooled temperature range, the layer of the foodstuffs into a second housing section of the plurality of housing sections;
• and
• forcing, in the second housing section, the stream of the gaseous medium to flow in a second direction through the layer of the foodstuffs, the second direction being different from the first direction.

A method for operating a tunnel freezer for freezing foodstuffs, the foodstuffs having a determined supercooled temperature range in which water in the foodstuffs is supercooled, the tunnel freezer comprising:

• a housing, comprising a plurality of housing sections;
• a conveyor unit configured to convey a layer of the foodstuffs through each housing section of the plurality of housing sections;
• each housing section, of the plurality of housing sections, comprising:
• a ventilator for providing a stream of a gaseous medium;
• and
• a cooling unit arranged to cool the gaseous medium in the stream;
• wherein:
• a first housing section, of the plurality of housing sections, is configured to force the stream of the gaseous medium to flow in a first direction through the layer of the foodstuffs,
• a second housing section, of the plurality of housing sections, is configured to force the stream of the gaseous medium to flow in a second direction through the layer of the foodstuffs, the second direction being different from the first direction;
• the method comprising:
• cooling, in the first housing section, the layer of the foodstuffs until an average temperature of the foodstuffs is in the supercooled temperature range;
• and
• conveying, when the average temperature of the foodstuffs is in the supercooled temperature range, the layer of the foodstuffs into the second housing section.