Ultra-high-temperature processing

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A brick of French UHT milk

Ultra-high temperature processing or (less often) ultra-heat treatment (both abbreviated UHT) is the partial sterilization of food by heating it for a short time, around 1-2 seconds, at a temperature exceeding 135°C (275°F), which is the temperature required to kill spores in milk.^[1] The high temperature also reduces the processing time, thereby reducing the spoiling of nutrients. The most common UHT product is milk, but the process is also used for fruit juices, cream, yoghurt, wine, soups, and stews.^[1]UHT milk was invented in the 1960s, and became generally available for consumption in 1970s.^[2]

High heat during the UHT process can cause Maillard browning and change the sensory characteristics of dairy products.^[3]

UHT milk has a typical shelf life of six to nine months, until opened. It can be contrasted with HTST pasteurization (high temperature/short time), in which the milk is heated to 72°C (161.6°F) for at least 15 seconds.

1 Nutrition: UHT vs Pasteurized Milk
2 Popularity
3 Crohn's disease
4 Environment
5 UHT and Cosmetics
6 See also
7 External links
8 References

[edit] Nutrition: UHT vs Pasteurized Milk

Calories: depending on variety of milk, UHT milk contains the same amount of calories as pasteurized milk.
Calcium: UHT and pasteurized milk contain the same amount of calcium.
Folate: UHT milk contains less folate then pasteurized milk. UHT milk contains 1 mcg of folate per 100g, while pasteurized contains 9 mcg.^[4]
Vitamin B12, Vitamin C and Thiamin: Some nutritional loss can occur in UHT milk.^[5]

[edit] Popularity

UHT milk has seen large success in much of Europe, where across the continent as a whole 7 out of 10 Europeans drink it regularly.^[6] In fact, in a hot country like Spain, UHT is preferred due to high costs of refrigerated transportation and "inefficient cool cabinets."^[7] Europe's largest manufacturer, Parmalat, had $6 billion of sales in 1999.^[6] However, these figures conceal wide variations:

UHT milk as a percentage of total consumption: ^[8]

Austria 20.3
Belgium 96.7
Britain 8.4
Czech Rep 71.4
Denmark 0.0
Finland 2.4
France 95.5
Germany 66.1
Greece 0.9
Hungary 35.1
Ireland 10.9
Italy 49.8
Netherlands 20.2
Norway 5.3
Poland 48.6
Portugal 92.9
Slovakia 35.5
Spain 95.7
Sweden 5.5
Switzerland 62.8

In June 1993, Parmalat introduced its UHT milk to the United States. ^[9] However in the North American market, consumers have been uneasy about consuming milk which is not delivered under refrigeration, and have been much more reluctant in buying it.^{[citation needed]} To combat this, Parmalat is developing UHT milk in old-fashioned containers.^{[citation needed]} Many milk products in North American foods are made using UHT milk, such as McDonalds McFlurries.^{[citation needed]} UHT milk is also used on airplanes.^{[citation needed]}

UHT milk is sold on American military bases in Puerto Rico, Panama and Korea due to limited availability of milk supplies and refrigeration.^[10]

[edit] Crohn's disease

"Crohn's disease is a disorder of the bowel system, which causes abdominal pain, cramping, fatigue and diarrhea. Researchers at St. George's Hospital Medical School in London say they've found a common link between the disease and milk: Mycobacterium avium paratuberculosis bacteria, or MAP."^[11]
However, "researchers caution consumers not to stop drinking milk but rather that people with Crohn's and their close relatives start drinking UHT milk — the long-lasting milk that can sit at room temperature for years. 'UHT involves higher pasteurization temperatures, which probably destroys MAP,' said the scientists."^[12]

[edit] Environment

In the UK, the Dairy Farmers have set out to reduce greenhouse gasses by 20%-30% by the year 2020. One of the measures proposed was to achieve a 90% UHT milk production.^[13] The Officials at the Department for Environment, Food and Rural Affairs believe that this would significantly cut the need for refrigeration, and benefit the environment by reducing green house emissions.^[14] However the milk industry opposed this, and the proposition was quickly abandoned.

In Thailand, the environmental concerns are over the UHT milk cartons. Tetra Pak (Thai) Ltd. was due to "establish Southeast Asia's first recycling plant for used UHT drink containers".^[15]

[edit] UHT and Cosmetics

Recently the application of UHT technology has been pioneered by a French company, Laboratoire Cosmétique CL Tech, in the sterilization of cosmetic products, eliminating the need for the use of preservatives, such as parabens. ^[16] The company is currently searching for international manufacturers, with access to global markets, to broaden the use of this technology. ^[17]