Cette hotte comprend une enveloppe (42) dotée d'un sommet (43), de bords opposés (44, 45, 46, 47) ainsi que de parois latérales opposées (48, 49, 50, 51) qui soutiennent un séparateur à impact (13) pourvu d'orifices. Le gaz est mélangé au cryogène solide ou liquide dans la hotte de contact ; ce mélange étant ensuite conduit au séparateur à impact.
Food products are frozen or cooled within a housing chamber (20) defined by side walls (23, 24) between an ceiling (21) and floor (22) and having a cryogen supply, a food products conveyor (38) extending into the chamber disposed between the ceiling and floor, by transporting the food products on the conveyor, the chamber containing at least one impingement hood (10) disposed above the conveyor; the impingement hood including a shell (42) including a top (43), opposed edges (44, 45, 46, 47) and opposed side walls (48, 49, 50, 51) supporting an impinger (13) containing openings.patents-wipo patents-wipo