SAETT OCH ANORDNING FOER KONTINUERLIG STERILISERING AV EN FLYTANDE MJOELKBASERAD PRODUKT

摘要

A method of sterilizing a liquid milk based product comprises indirect preheating of the product and final heating to a sterilization temperature 140-150 DEG C by direct steam injection. The product is cooled by so called flash-cooling at which steam corresponding to the added amount of steam is evaporated and the product is further cooled by indirect cooling. It is now proposed that the product prior to the flash-cooling is cooled from the sterilization temperature of 140-150 DEG C to a temperature in the range 90-120 DEG C in an indirect, first cooling step after which the product is cooled by flash-cooling to a temperature of 70-85 DEG C. The arrangement for sterilization comprises a balance vessel (1) connected to an indirectly working first heat exchanger (4) for heating of the milk based product. A steam injection nozzle (6) is arranged in a pipeline leading from the heat exchanger (4). After the steam injection nozzle (6) there is a holding section (8) and a vacuum vessel (10) in which the product is cooled by flash-cooling. A further indirectly working heat exchanger (9) for cooling of the product is connected between the holding section (8) and the vacuum vessel (10).