Pasteurisering

Pasteurisering is a process named after its inventor, Louis Pasteur, a French scientist. It involves heating a liquid to a specific temperature for a set period of time to kill harmful microorganisms such as bacteria, viruses, and yeasts. The primary goal of pasteurisering is to improve the safety and shelf life of consumable products, particularly milk and dairy products, but it is also applied to juices, eggs, and other liquids.

The most common method, called high-temperature short-time (HTST) pasteurisering, involves heating milk to at least 72 degrees Celsius (161 degrees Fahrenheit) for 15 seconds. Another method, called vat pasteurisering or low-temperature long-time (LTLT) pasteurisering, heats milk to at least 63 degrees Celsius (145 degrees Fahrenheit) for 30 minutes. Ultra-high temperature (UHT) pasteurisering heats liquids to even higher temperatures for very short durations, allowing for longer shelf stability without refrigeration.

Pasteurisering significantly reduces the risk of foodborne illnesses caused by pathogens like Listeria, Salmonella, and E. coli. While it kills most harmful bacteria, it does not sterilize the product, meaning some spoilage microorganisms may survive, and the product will eventually spoil if not stored properly. The process is designed to be effective against pathogens without significantly altering the taste, nutritional value, or texture of the product. It is a widely adopted public health measure in food processing worldwide.