The food lab better home cooking through science ( PDFDrive ) 94

Q: What’s inside the egg that makes it so culinarily useful? There are two basic parts to an egg: yolk and white The yolk is the nutritive source for the developing embryo, and it accounts for about 75 percent of the calories in an egg Yolks may appear rich and fatty, but, in fact, they are essentially sacks of water that contain dissolved proteins, along with larger masses of protein and fat linked together with lecithin, an emulsifying molecule that allows fat and water molecules get along together harmoniously We’ll get back to that in a moment The white is also mostly water, along with a few proteins —the most important being ovalbumin, ovomucin, and ovotransferrin, which give it its unique capacity to both set when cooked and be whipped into stiff, shaving cream–like peaks Because the proteins in eggs are already dissolved and spread out in a liquid, it is very easy to incorporate them into other foods—much more than, say, meat proteins, which are relatively firmly set in place in relation to one another (Have you ever tried whipping a steak? I have It doesn’t work.) Additionally, the fact that eggs contain such a wide variety of proteins, each of which behaves in a slightly different way when heat or mechanical action is applied, means that as a cook, you have great control over the final texture of your finished dish Eggs cooked to 140°F, for example, will be soft and custard-like, while those cooked to 180°F will be bouncy and firm Labeling: Size and Quality Q: Eggs come in a few different sizes at the supermarket Which ones should I be reaching for? ...There are two basic parts to an egg: yolk and white The yolk is the nutritive source for the developing embryo, and it accounts for about 75 percent of the calories in an egg... when cooked and be whipped into stiff, shaving cream–like peaks Because the proteins in eggs are already dissolved and spread out in a liquid, it is very easy to incorporate them into other foods—much more than, say, meat proteins,... are relatively firmly set in place in relation to one another (Have you ever tried whipping a steak? I have It doesn’t work .) Additionally, the fact that eggs contain such a wide variety of proteins,