An egg wash is used to make pastry (such as a
crust) shine, and aids in browning. An egg wash is also used to
bind parts together (such as when patching holes or cracks in your
crust, or to seal the edges of the top and bottom crusts together, or to
add fancy cut-outs), or to
moisture-seal the bottom crust when blind baking so it doesn't get
soggy when the pie filling is added.
An egg wash is just beaten egg and maybe a little bit of liquid (usually milk or water), which is mixed together and brushed (or "washed") onto the pie dough's surface with a pastry brush.
Be careful not to brush it on too thickly, or it can dribble down between your crust and the pie pan, essentially gluing them together. And if it's too thick and goopy, whatever you're trying to seal won't seal, it will just get mushy.
“'Why' and 'How' are words so important they cannot be too often used.” Napoleon Bonaparte
|For this result:||Make an egg wash with:|
|Shiny||whole egg, salt|
|Faint Shine||whole egg, milk|
|Matte, golden-brown||whole egg, water|
|Shiny, golden-brown||egg yolk, water|
|Shiny, golden-brown||egg yolk, salt|
|Shiny, dark||egg yolk, cream|
|Crisp, pale||egg white|
|Matte, golden-brown||heavy cream or half & half|
|Faint shine, golden-brown||olive oil|