Pulling Proteins Together . . .

Appears in
On Food and Cooking

By Harold McGee

Published 2004

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The raw egg begins as a liquid because both yolk and white are essentially bags of water containing dispersed protein molecules, with water molecules outnumbering proteins 1,000 to 1. As molecules go, a single protein is huge. It consists of thousands of atoms bonded together into a long chain. The chain is folded up into a compact wad whose shape is maintained by bonds between neighboring folds of the chain. In the chemical environment of the egg white, most of the protein molecules accumulate a negative electrical charge and repel each other, while in the yolk, some proteins repel each other and some are bound up in fatprotein packages. So the proteins in a raw egg mostly remain compact and separate from one another as they float in the water.