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Food Microbiology
Pasteurization is the process of heating liquids
for the purpose of destroying bacteria, protozoa, molds,
and yeasts. The process was named after its
creator, French chemist and microbiologist Louis Pasteur. Pasteurization is not intended
to kill all pathogenic micro-organisms in the
food or liquid. Instead, pasteurization aims to reduce the number of viable pathogens
so they are unlikely to cause disease. Commercial-scale sterilization of food
is not common because it adversely affects the taste and quality of the product.
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There
are two main types of pasteurization used today: High Temperature/Short Time (HTST) and
Extended Shelf Life (ESL) treatment. Ultra-high temperature (UHT
or ultra-heat treated) is also used for milk treatment. In the HTST process,
milk is forced between metal plates or through pipes heated on the outside by
hot water, and is heated to 71.7 °C (161 °F) for 15-20 seconds. UHT processing
holds the milk at a temperature of 138 °C (250 °F) for a fraction of a second.
ESL milk has a microbial filtration step and lower temperatures than HTST. Milk
simply labeled "pasteurisation” is usually treated with the HTST method,
whereas milk labeled "ultra-pasteurisation” or simply "UHT" has
been treated with the UHT method.
Products that can be pasteurized
Almonds,
Apple cider ,Beer
,Canned food ,Crabs
Eggs, Honey
, Juice, Maple Syrup,
Milk, Palm wine,
Soy sauce, Sports drinks,
Vinegar, Water,
Wine.
Sterilization refers to any process that effectively kills or eliminates transmissible agents (such as fungi, bacteria, viruses, and spore forms etc.) from a surface, equipment, foods, medications, or biological culture medium. The first application of sterilization was thorough cooking to effect the partial heat sterilization of foods and water. Cultures that practice heat sterilization of food and water have longer life expectancy and lower rates of disability. Canning of foods by heat sterilization was an extension of the same principle. Ingestion of contaminated food and water remains a leading cause of illness and death in the developing world, particularly for children.
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