UHT processing was developed as early as 1938, aseptic processing, which enabled the distribution of milk without refrigeration, commenced only in 1961.
The various types of heating systems such as steam injection and infusion, were developed for UHT heating to achieve a better sterile product, however, the difficulty of packaging the sterile milk without recontamination into suitable containers for transport hindered the commercialization of UHT products until 1953.
The first system consisting of indirect heating which milk was indirectly heated at 125ºC with a holding time of 6 minutes was manufactured in 1893, only 11 years after the first commercial pasteurizer was used.
Patented in 1912, the continuous flow direct heating method mixed steam with milk to achieve temperatures of 130 to 140ºC. Development was hindered due to contamination potential without commercial aseptic systems. This process avoided the burn on encountered in the indirect heating.
The development of aseptic processing in the United States started through the efforts of C. Olin Ball, and hot-cool-fill process was commercialized in 1938 for a chocolate milk beverage.
UHT processed milk produced in an innovative heater known as Uperiser, and aseptically packed in cans, was first developed in Switzerland in 1953, through the collaborative efforts of a dairy company and a machinery manufacturing firm.
A similar heating technique has employed for long-shelf-life milk but this has aseptically packaged into a tetrahedral paperboard carton for sale in Switzerland in 1961. Tetra Pak pioneered its own continuous UHT process and aseptic packaging systems, and so kick started the growth of the UHT milk segment.
In 1964, ice cream mix and concentrated milk formulations UHT heat treated with direct heat and packaged in four-liter cans. This represented the first commercial aseptic production in Australia.
Historical Development of UHT Milk
