In order to overcome the limitations and problems that earlier methods and apparatus / systems have experienced, a method for, in particular rapid, cooling of at least one fluid (15) is proposed, comprising - providing a source (12) of the fluid (15) to be cooled； - flowing the fluid (15) to be cooled through a pipeline (20)； - injecting (26) cryogen into the fluid (15)； - first measuring a temperature of the flowing fluid (15) in the pipeline (20) with a first temperature sensor (40) after the injecting (26) the cryogen； - second measuring the temperature of the flowing fluid (15) with a second temperature sensor (56) after the first measuring； and - adjusting a flow rate of the fluid (15) through the pipeline (20) responsive to a difference between temperature measurements of the first temperature sensor (40) and the second temperature sensor (56) while maintaining a rate of the injecting (26) of the cryogen and maintaining a temperature difference between the first temperature sensor (40) and the second temperature sensor (56). A corresponding apparatus (10) for, in particular rapid, cooling of at least one fluid (15) is also proposed.
