In order to overcome the limitations and problems that earlier apparatus and processes / methods have experienced, an impinger (16) is proposed for cooling or freezing products (40), in particular individually quick frozen (IQF) products, for example IQF food products, comprising an impingement plate (37) containing openings (46) for directing impingement jets of a mixture (34) of gas and solid or liquid cryogen toward the products (40) conveyed or transported on a conveyor (13), wherein the openings (46) in aggregate comprise an open area of about seven percent to about twelve percent of the total surface area of the impingement plate (37), and wherein the impingement plate (37) provides a back pressure restriction in a circulation path of the mixture (34) of about 220 Pa to about 475 Pa, in particular of about 270 Pa to about 475 Pa. A corresponding cooling or freezing process/method is also proposed.
