This document discusses pasteurization of milk. It begins with definitions of pasteurization from international organizations. It then provides a brief history of pasteurization dating back to the 11th century. The document outlines the main reasons for milk pasteurization including safety, shelf life, and flavor preservation. It describes the most common pasteurization methods: low-temperature long-time (LTLT) batch pasteurization, high-temperature short-time (HTST) flash pasteurization, and ultra-high temperature (UHT) pasteurization. It also discusses pathogens commonly found in raw milk and concludes with references.