There are many food safety guidelines in place in order to prevent contamination of food, one of which is pasteurisation. Eggs are temperature-sensitive and have the potential to harm or even kill if they are contaminated, making them a prime candidate for pasteurisation. But not all eggs you can buy at the store are pasteurised. If the egg carton doesn't say they are pasteurised then they aren't.
What is Pasteurization
Pasteurisation is the process of killing bacteria in food items with heat. Milk, juices and eggs are common food items that go through a pasteurisation process. The High-Temperature-Short-Time Treatment (HTST) pasteurises food in short bursts of just seconds at a very high temperature. And Low-Temperature-Long-Time Treatment (LTLT) uses a lower temperature for a longer period of time to ensure the same end result.
The Process of Pasteurizing Eggs
Pasteurising eggs can be a tricky process because eggs will cook at a temperature of 62.8 degrees Celsius. For this reason, eggs must be pasteurised at a lower temperature for a longer period of time (LTLT). They are pasteurised at 54.4 degrees Cor 45 minutes if they are being sold in the shell. Dried eggs are treated for a full seven days at 54.4 degrees Celsius.
Why Eggs are Pasteurized
The biggest reason anything is pasteurised is to kill pathogenic bacteria that can cause disease and food poisoning. For eggs, one of the biggest risks is salmonella poisoning. Though rare, salmonella can make victims extremely ill and in some cases even kill them. Children, the elderly and those already suffering from a pre-existing condition are at greatest risk for salmonella poisoning or death. One advantage of pasteurised eggs is that they can be consumed raw, though unpasteurised eggs should not be consumed raw because of the risk of salmonella and other food poisoning.
Post-Pasteurization Egg Contamination
Although eggs that have been pasteurised are safe to eat and free of pathogens, that doesn't mean they can't get contaminated later. Eggs are very temperature sensitive. If you do not refrigerate them properly they can still become contaminated. If you handle the eggs with dirty hands, utensils or cooking surfaces, they can also become contaminated that way. Always refrigerate your eggs and make sure you use clean hands, knives and other cooking utensils before, during and after handling pasteurised eggs.