Cold egg whites, superfine sugar and cream of tarter are ingredients for a successful meringue. Beyond mere ingredients, there are certain techniques for preparing meringue that help yield respectable results.
A meringue is essentially sugar suspended in egg whites beaten to soft, glossy peaks. Cold egg whites tend to whip up more readily than warm egg whites and have better structure. Traditionally, French cooks prepare meringue by hand, whipping egg whites in copper bowls. Copper bowls contain elements that bind to egg white protein molecules, leaving fewer of the molecules free to denature.
Fewer denatured egg white protein molecules means less coagulation, fewer clumps and more stability. When making meringue without a copper bowl, a dash of cream of tarter reacts with the egg whites in much the same way.
Fat from egg yolks is an enemy of perfectly whipped egg whites, so carefully separating whites from yolks is important. Bits of egg shell also negatively impact whipped egg whites, and Martha Stewart suggests gently cracking eggs on a flat surface to reduce the risk of introducing tiny shards of egg shell.
Sugar adds flavor and an additional amount of reinforcement to whipped egg whites. Texture is key, so sugar that dissolves well in egg whites is preferable, such as superfine. In the absence of superfine, granulated sugar processed in a food processor for one to two minutes until powdery suffices.