Pastry – Why Does Pâte à Choux Puff Up?

pastry

Why does pâte à choux puff up so perfectly?
What are the ingredients or the science behind it that can make that happen?

Best Answer

A choux is an interesting batter that is created in a way that maximizes gluten structure. It is essentially cooked twice. You combine and heat water and butter, then add flour and continue cooking the resulting paste. That paste forms a ball, and then several eggs are beaten in. This batter is then piped onto a sheet and baked. In addition to the gluten structure, the initial cooking also causes the starches to gelatinize, further reinforcing the structure. In essence, you have created a deflated balloon. When the piped shapes are baked, steam develops and inflates the "balloon." It's all explained quite clearly right here.