Pasteurization is a process where food is heated to 140°F, killing harmful bacteria. Egg yolks would normally start to cook at 140°F, but you can use a microwave to pasteurize egg yolks without cooking them, so they can safely be used in mayonnaise and other preparations requiring raw egg yolks.
How it works is by adding acid to the egg yolks — either in the form of lemon juice or vinegar. Adding acid raises the temperature at which egg yolks cook, so you can heat them to 140°F, killing the bacteria, but without cooking the egg.
Some grocery stores may sell pasteurized eggs, but if not you can do it yourself.
Here is How
IMPORTANT - You will need at least 3 clean whisks
Separate two eggs and collect the yolks in a microwave-safe glass bowl. Whisk the yolks thoroughly using the first of your three clean whisks.
Add 1 Tbsp lemon juice and whisk again.
Add 2 Tbsp water and whisk again. Seal bowl with plastic wrap and place it in the microwave.
NOTE: The current whisk should be set aside now. You'll need to have the next two ready to go in quick succession.
Heat the egg mixture on high until the surface begins to rise. Once you see this, cook for 8 more seconds, then immediately remove the bowl from the microwave, remove the plastic wrap and whisk the yolks vigorously with a clean whisk.
Immediately return the bowl to the microwave and heat on high again until the surface begins to rise. Continue for 8 more seconds, them remove and whisk vigorously with another clean whisk until the mixture is smooth and creamy.
These egg yolks are now safe to use in mayonnaise or other raw-egg preparations.