For most people, eating raw eggs is associated with bodybuilders, fitness enthusiasts, and training montages from '80s sports movies. But when you think about it, there are quite a few recipes that call for raw eggs. Think mayonnaise, steak tartare, and even some chocolate mousse recipes. So even if you’re not Arnold Schwarzenegger or Sylvester Stallone, you could find yourself wanting to eat something that’s made with raw eggs, and if you do, you’ll want to make sure those eggs are safe to eat.
Why pasteurise eggs?
Raw eggs can carry a dangerous strain of bacteria called Salmonella. Salmonella is usually found on the outside of the eggshell, and is transferred to the edible parts of the egg once it has been cracked. On some occasions, however, it has been detected in the white and yolk of a completely intact egg, so even freshly-cracked eggs may not be safe.
There are billions of eggs produced annually in the USA, the vast majority of which are safe, but the USDA still estimates that around 79,000 cases of food-borne illness and 30 deaths can be traced to eating contaminated eggs each year. For these reasons, the CDC recommends that vulnerable groups including pregnant women, children and infants, adults over 65 and the immunocompromised should avoid eating raw eggs altogether.
For the rest of us, however, pasteurisation, a process that involves exposing the eggs to moderate heat in order to kill pathogens, can dramatically reduce the risk of food-borne illness. You can buy pre-pasteurised eggs from the store, and they are also available in liquid form, sold in cartons, although these are not suitable for recipes that call for the eggs to be separated.
If you can’t get hold of pasteurised eggs from your local store, you can try pasteurising regular eggs at home. It may sound like a complicated chemistry experiment, but it’s actually pretty straightforward once you know how. Follow our simple how-to guide and you’ll soon be pasteurising eggs like a pro.
How to pasteurise egg yolks
Follow these simple instructions to pasteurise egg yolks in three easy steps.
1. Mix the eggs with liquid or sugar
Add the egg yolks to a saucepan, and mix with 2 tablespoons per egg of either liquid or sugar taken from your recipe. For example, if you have a sweet recipe with 2 egg yolks, you should add 4 tbsp of the sugar from the recipe. If the recipe does not contain enough liquid or sugar, you will have to increase the amount.
2. Cook over a low heat until the mixture reaches 160°F
Cook over a very low heat, stirring gently with a spatula throughout to prevent the egg from coagulating. Check the temperature regularly with a food thermometer, and remove from the heat once it reaches 160°F.
3. Cool if needed, then use immediately
If you are using the yolks in a hot recipe, mix them in with your other ingredients immediately. If your recipe is cold, use them as soon as they have returned to room temperature.
How to pasteurise egg whites
The procedure for pasteurising whites is very similar to that for yolks, but there are some slight differences.
1. Mix the eggs with liquid or sugar
Fill a large saucepan with water and bring to the boil. Place your egg whites in a heat proof bowl and mix with either 2 tablespoons of water per white, or 2 tablespoons of water and 1/16 teaspoon of cream of tartar per egg. Place the bowl in the pan of water, to make a bain-marie.
2. Cook over a low heat until the mixture reaches 160°F
Cook over a very low heat, stirring gently with a spatula throughout to prevent the egg from coagulating. Check the temperature regularly with a food thermometer, and remove from the heat once it reaches 160°F.
3. Cool if needed, then use immediately
If you are using the whites in a hot recipe, mix them in with your other ingredients immediately. If your recipe is cold, use them as soon as they have returned to room temperature.
How to tell if an egg has been pasteurised
It is impossible to tell if an egg has been successfully pasteurised just by looking at it. The best you can do is make sure that it reaches the correct internal temperature. For this reason pasteurising eggs in their shells at home is not recommended, as it is difficult to accurately gauge their internal temperature.