Adding an egg wash to baked goods will enhance them by providing a shiny surface that browns attractively. Use an egg wash on breads or pies to give them a professional bakery finish. Think of this as creating the right surface appearance. Visually, it's like using a semi-gloss paint for trim instead of flat in your house. Why go to all of that trouble? Because that little bit of gloss just makes the surface look better. Think of egg wash as applying the right amount of shine and color.
- 1 egg yolk
- pinch of salt
- 1 to 2 tablespoons of water
Separate an egg and put the white aside for another use. Egg whites can be added to an omelet to make them lighter, used in angel food cake, or to make a meringue. Be sure the white of the egg is in a well sealed air-tight container and stays refrigerated until used, which should be within a week (see http://www.marthastewart.com/272253/saving-eggs).
With the egg yolk in a prep bowl that allows enough room for beating, add the water and salt. A literal pinch of salt is often defined as 1/8 teaspoon but this should be about half that amount. Beat the ingredients until they make a consistent liquid. The thickness of an egg wash is where some judgment comes into play The wash should be loose but not watery. The object is to have something that will stick to a pastry brush and not run off when brushed on the baking item. The egg wash must also not be so thick that it clumps when applied. I find that the salt keeps the wash from darkening baked goods too much.
Apply the egg wash using a soft pastry brush once bread has risen and formed a crust or pies are nearly cooked. Generally, about in the last 10 minutes of baking is the right moment. Apply egg wash with the baked item in the oven. This allows the oven to cool slightly but keeps the baked good warm while the wash is applied. Be neat--egg wash can make a mess if dripped onto a hot oven surface--and don't get burned. If the wash leaves streaks, loosen it with a few more drops of water and quickly apply again. Close the oven and allow the baking item to brown.