Process and apparatus for quick-freezing of food products

Claim 1

Apparatus for quick freezing liquid or pasty food products by adding same to a bed of carbon dioxide snow, the mixing of the food product being performed in three zones, respectively, in a first zone for freezing where the product to be frozen is mixed with the carbon dioxide snow, then in a second zone wherein separation of frozen granules of suitable size from fine snow and fines of frozen product occurs, and a third zone of sublimation of the excess snow and stabilization of the temperature of the frozen product by the regulated addition of an additional quantity of said liquid or pasty food product to the third zone to regulate the removal temperature to that desired for the frozen granules, comprising a large, covered, insulated, parallelipipedic vat, divided into said three zones, an input zone corresponding to said first zone, a central zone corresponding to said second zone, and an end zone corresponding to said third zone, said vat being equipped along its entire length with a rotor provided with arms arranged so that the movement of the product in the input zone has at most a slight axial downstream direction, the rotor arms in the central zone of the apparatus comprising means to move large frozen food particles downstream and small frozen food particles upstream, said means including a double series of blades spaced radially apart on said arms, the outer blades being oriented to move small frozen food particles upstream and the inner blades being oriented to move large frozen food particles downstream, and the number of rotor arms being less in the end zone; the central and end zones of the vat being partially separated by a partition and connected by a chute in this partition; the upper part of the vat being provided in the input zone with input pipes for the food product regularly distributed around a flared pipe for the carbon dioxide snow, in the central zone of the device means for recovering the gaseous carbon dioxide and in the end zone a spraying means for the addition of additional liquid or pasty food product to be frozen.