Pasteurization is the process of food preservation by heating food just enough to destroy most pathogens (usually to less than 100°C). It is named after Louis Pasteur, a French chemist who in 1867 proved that wine and vinegar could be preserved by heating it to 55°C.
Pasteurization is common for dairy products, to stop lactic acid forming bacteria, which naturally occur in milk, from turning the milk sour. The traditional process is vat pasteurization, whereby milk in a large tank is heated to 63º C for at least 30
minutes. It is now used primarily in the dairy industry for preparing
milk for making starter cultures.
New technologies include High Temperature Short Time Pasteurization (HTST), which uses metal
plates and hot water to raise milk temperatures to at least 72ºC for
not less than 15 seconds, followed by rapid coolingor Ultra Pasteurization (UP), whereby milk is heated to 138ºC for 2 seconds.
