Ultra-high-temperature processing

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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 most common UHT product is milk, but the process is also used for fruit juices, cream, yogurt, 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 taste and smell 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.

Contents 1 Nutrition: UHT vs Pasteurized Milk 2 Popularity 3 Environment 4 Cultural References 5 See also 6 External links 7 References

[edit] Nutrition: UHT vs Pasteurized Milk

Calories: depending on variety of milk, UHT milk contains the same number of calories as pasteurized milk.
Calcium: UHT and pasteurized milk contain the same amount of calcium.
Folate: UHT milk contains less folate than pasteurized milk. UHT milk contains 1 μg of folate per 100g, while pasteurized contains 9 μg.^[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 as in most European countries High Temperature/Short Time (HTST) pasteurised milk is more popular.^{[citation needed]}

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

Austria 20.3%  Belgium 96.7%  Czech Republic 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%  United Kingdom 8.4%

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 and Korea due to limited availability of milk supplies and refrigeration.^[10]

UHT milk gained popularity in Puerto Rico as an alternative to pasteurized milk due to environmental factors.^{[citation needed]} For example, power outages after a hurricane can last up to 2 weeks, during which time regular pasteurized milk would spoil from lack of refrigeration.

[edit] Environment

In the UK, the government had proposed a 90% UHT milk production target by 2020^[11] which they believed would significantly cut the need for refrigeration, and thus benefit the environment by reducing green house emissions.^[12] However the milk industry opposed this, and the proposition was quickly abandoned.

In Thailand, environmental concerns relate to UHT milk cartons. Tetra Pak (Thai) Ltd. is due to "establish Southeast Asia's first recycling plant for used UHT drink containers".^[13]

[edit] Cultural References

In Neal Stephenson's novel Cryptonomicon, the character Randy Waterhouse eats Cap'n Crunch cereal in a very specifically described manner, with UHT milk that has been chilled nearly to its freezing point.

[edit] See also

• Pasteurization
• Sterilization
• Milk

[edit] External links

• An article focusing on the negative aspects of UHT milk from the Weston A. Price Foundation
• Milk in a Box. From: Interesting Thing of the Day

[edit] References