The move is on for ultra-high temperature (UHT) sterilization, which will extend the shelf life of milk and other dairy products. UHTsterilization is being used because consumers are buying more dairy products in bulk, dairy operations are becoming larger, and population expansion is increasingly causing consumers to be located in more remote locations throughout the world. Traditionally, milk is pasteurized at 180- 185°F (about 85°C) and refrigerated. Other dairy products are commercially sterilized by subjecting product to temperatures in excess of 100˚C, and then packaging it in airtight containers. The basis of UHT is sterilization of the product before packaging, then packaging it in pre-sterilized containers in a sterile atmosphere. Processing dairy products in this manner, using temperatures exceeding 135˚C, permits a reduction in the required hold time to 2-to-5 seconds, and yields a shelf stable product that can be stored for extended period of time at ambient temperature.

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