Cryogenic tunnels use liquefied carbon dioxide (LCO2) or liquefied nitrogen (LIN) for continuous cooling and freezing. A conveyor belt moves the product along the tunnel. Controlled injection of a cryogenic liquefied gas that immediately evaporates lowers the temperature in the tunnel. The latent heat of evaporation is the main source of cooling energy. Turbulence fans spread the gas in the tunnel in a controlled way and efficiently transfer the cold to the product’s surface. Exhaust fans extract the residual gases.