flash-heating of milk//ultra-heat treatment of milk,
Ultra-high temperature processing (UHT), ultra-heat treatment, or ultra-pasteurization is a food processing technology that sterilizes liquid food, chiefly milk, by heating it above 135 °C (275 °F) – the temperature required to kill spores in milk – for 1 to 2 seconds. UHT is most commonly used in milk production, but the process is also used for fruit juices, cream, soy milk, yogurt, wine, soups, honey, and stews. UHT milk was first developed in the 1960s and became generally available for consumption in the 1970s.
The heat used during the UHT process can cause Maillard browning and change the taste and smell of dairy products. An alternative process is HTST pasteurization (high temperature/short time), in which the milk is heated to 72 °C (162 °F) for at least 15 seconds.
UHT milk packaged in a sterile container, if not opened, has a typical unrefrigerated shelf life of six to nine months. In contrast, HTST pasteurized milk has a shelf life of about two weeks from processing, or about one week from being put on sale
In the heating stage, the treated liquid is first pre-heated to a noncritical temperature (70–80 °C [158–176 °F] for milk), and then quickly heated to the temperature required by the process.
More or so, over the last few decades, milk processing and milk packaging ways have drastically taken new heights. With the onset of UHT or Ultra-high Temperature sterilization of milk, also called Aseptic Milk packaging, milk is now safe minus the refrigeration. Air sealed in shelf-safe cartons after flash heating (heating at high temperatures for a few seconds), UHT milk processing is safe and convenient for everyone today since life is on the go and not everyone can stay home to enjoy that cup of milk from the fridge. UHT milk packaging is environment friendly and in this way of processing milk, the nutrients stay same. There is no loss of calcium, minerals or Vitamins in UHT milk processing.