Uht

UHT, or Ultra-High Temperature processing, is a method of sterilizing liquid foods by heating them to very high temperatures for a short time and then cooling rapidly. The typical temperature range is about 135 to 150°C (275 to 302°F) for 2 to 5 seconds. This treatment aims to destroy microorganisms and spores sufficiently to achieve commercial sterility, allowing the product to be stored at ambient temperatures in sealed, aseptic packaging.

The process commonly uses rapid heat exchange to heat and then cool the product, often in a continuous flow through steam or hot water systems. Aseptic packaging, such as cartons or sterilized bottles, prevents post-process contamination and enables long shelf life without refrigeration before opening.

Compared with conventional pasteurization (such as HTST: high-temperature short-time, around 72°C for 15 seconds), UHT applies higher heat for a shorter duration. The result is a products that can be stored unopened at room temperature for months, but the intense heat can impart a slightly cooked flavor to some dairy beverages. Many UHT products are marketed as long-life or shelf-stable versions of milk, cream, and other liquids.

Applications extend beyond dairy to plant-based milks, fruit juices, soups, and sauces. Shelf life for unopened UHT products is typically several months to around a year, depending on the product and packaging. Once opened, most UHT beverages require refrigeration and should be consumed within a few days.

Safety and labeling follow standard regulatory requirements; products are designed for sterility before packaging, provided the packaging remains intact. UHT is a widely used method for extending shelf life and simplifying distribution, especially in areas with limited cold-chain infrastructure.