The process of ______ is used to increase shelf life of milk by destroying disease causing microorganisms.

Pasteurisation is a heat-treatment process developed by Louis Pasteur that is widely used to improve the shelf life and microbiological safety of milk. In this process, milk is typically heated to about $72^{\circ }\text{C}$ for 15 seconds (High-Temperature Short-Time or HTST method) or $63^{\circ }\text{C}$ for 30 minutes, followed by rapid cooling to eliminate pathogenic microorganisms without significantly altering nutritional quality.