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How is pasteurization different from sterilization?

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Painting by Albert Edelfelt showing Louis Pasteur in his laboratory, holding a glass flask and examining it intently, surrounded by scientific equipment on a workbench. — Louis Pasteur In the 19th century Louis Pasteur's work established the germ theory of disease, proving that microorganisms cause fermentation and sickness, which led to the development of pasteurization, aseptic techniques in medicine, and effective vaccines for diseases such as rabies. (Painting by Albert Edelfelt, 1885.)

The primary difference between pasteurization and sterilization lies in the intensity of the heat treatment and the resulting microbial state of the product.

Temperature: Pasteurization typically uses mild heat, usually below 100 °C (212 °F), to preserve the sensory and nutritional qualities of food. In contrast, sterilization employs higher temperatures that exceed this limit.123
Microbial Destruction: Pasteurization is designed to destroy specific pathogenic microorganisms and reduce spoilage-causing organisms, but it does not eliminate all microorganisms or microbial spores. Sterilization is a more severe process that destroys all viable microorganisms and spores.1234
Shelf Life: Because pasteurization does not render a product sterile, pasteurized items often require additional preservation methods, such as refrigeration, to control microbial growth. Sterilized products generally have a significantly longer shelf life and may not require refrigeration until opened.231

Named for the French scientist Louis Pasteur, who pioneered the technique to prevent contamination in wine and beer, pasteurization remains a vital method for ensuring the safety of milk and other beverages.53