Pasteurization

Pasteurization treats packaged food, such as milk and fruit juice, with mild heat, usually under 100 degrees Celsius, to kill or deactivate the microorganisms and enzymes that cause spoilage or disease, though most bacterial spores survive the process; because the heat is mild, only minor changes occur to the food's nutrition and sensory qualities. It is named for the French microbiologist Louis Pasteur, whose research in the 1860s showed that heat treatment could deactivate unwanted microorganisms in wine, and by 1999 most liquid food was pasteurized through continuous systems using heat exchangers or direct or indirect application of hot water and steam. Non-thermal alternatives are also commercially available today, including high-pressure processing, also called pascalization, and pulsed electric field treatment.