The difference between fresh and long-life milk is the method of processing. Fresh(pasteurised) milk is heated to 74°C for 15 seconds. Longlife milk is heated to 140°C for two seconds and then packaged aseptically.The increased temperature at which long-life milk is treated results in a greater reduction in bacteria and heat-resistant enzymes in comparison to milk that undergoes regular pasteurisation –giving it an extended shelf life