Temperature

The egg whites’ temperature affects the foam’s stability. The best temperature is between 60 and 70 degrees. A cooler white is thicker and more viscous, trapping air more effectively; it may take longer to attain optimum volume but is less likely to be overwhipped.

The temperature at which the egg-white foam coagulates varies. It depends on how quickly it is heated, at what temperature and how much sugar is in the mixture. Yolks set at higher temperatures than whole eggs, and whites set at lower temperatures than yolks.