Pasteurized milk is milk that has been heat-treated, most commonly by the high-temperature short-time method at 72 °C for 15 seconds, to destroy pathogenic bacteria such as Salmonella, Listeria monocytogenes, and pathogenic Escherichia coli, along with most spoilage organisms. The process extends keeping quality to one to three weeks under refrigeration while retaining the milk’s taste and nutritional value far better than sterilisation. Because pasteurization is not sterilization, the milk must be kept continuously refrigerated and consumed within its use-by date to remain safe, and it must be protected from post-process contamination. Regulatory standards define the time-temperature combinations and phosphatase testing that verify adequate treatment.