Why it Works: Egg on Your Face
As proteins (think little springs) are heated, their structure changes. Add a little heat and proteins start to unwind and connect with neighboring proteins. Add more heat and proteins start to recombine and solidify. You see this last step when you fry an egg. The egg white changes from liquid to solid in a process called coagulation. All proteins coagulate when heated, but the temperature at which they solidify changes depending on their surroundings. For example, in this recipe, egg yolks are cooked with sugar and lemon juice. Normally egg yolks coagulate between 149º F and 158º F. However, here the sugar interferes with the proteins when they try to recombine. The lemon juice’s acidity changes the protein’s structure, making it harder for the proteins to reconnect. Because of these added ingredients, egg yolks can be cooked at a higher temperature without turning into sweet scrambled eggs.