What pasteurization method is most commonly used in the United States?

• A. HTST (high-temperature, short-time)
• B. LTLT (low-temperature, long-time)
• C. UHT (ultra-high temperature)
• D. Flash pasteurization

Answer: (A)

High-temperature, short-time pasteurization is used for most U.S. fluid milk because it reliably inactivates pathogens while preserving flavor and nutrients, and it fits well with high-volume, continuous processing. In practice, milk is heated to about 72°C (161°F) for roughly 15 seconds and then cooled rapidly. This combination provides strong safety with minimal quality loss, making it the standard method in large U.S. dairy plants.

Low-temperature, long-time pasteurization heats milk at a lower temperature for a much longer period, which can degrade taste and nutrients more and is less efficient at scale. Ultra-high-temperature processing gives a very long shelf life but can alter flavor and requires different packaging, so it isn’t the common method for everyday fresh milk in the United States. Flash pasteurization is often used interchangeably with HTST in some contexts, but HTST is the method that’s most widely adopted and recognized as the standard for U.S. milk processing.