In order to overcome the limitations and problems that earlier methods and apparatus have experienced, a method for freezing a product (24) in a cryogenic freezer (10) is proposed, said method comprising: - sensing (42, 44, 46, 48) at least one physical characteristic of the product (24) in real time； - providing a cryogenic substance (36) to the product (24) for heat transfer at said product (24)； - automatically self-adjusting the heat transfer at the product (24) responsive to the sensing (42, 44, 46, 48) the at least one physical characteristic； and - continuously self-adjusting the heat transfer for bringing the product (24) to a select temperature.
