Flash pasteurization, also called "high-temperature short-time" (HTST) processing, is a method of heat pasteurization of perishable beverages like fruit and vegetable juices, beer, wine, and some dairy products such as milk.
[1] Flash pasteurization is performed to kill spoilage microorganisms prior to filling containers, in order to make the products safer and to extend their shelf life compared to the unpasteurised foodstuff.
[2] It must be used in conjunction with sterile fill technology (similar to aseptic processing) to prevent post-pasteurization contamination.
[3] The liquid moves in a controlled, continuous flow while subjected to temperatures of 71.5 °C (160 °F) to 74 °C (165 °F), for about 15 to 30 seconds, followed by rapid cooling to between 4 °C (39.2 °F) and 5.5 °C (42 °F).
The standard US protocol for flash pasteurization of milk, 71.7 °C (161 °F) for 15 seconds in order to kill Coxiella burnetii (the most heat-resistant pathogen found in raw milk), was introduced in 1933, and results in 5-log reduction (99.999%) or greater reduction in harmful bacteria.