Role of eggs in choux pastry
Hi! I've been trying to understand the processes involved in making choux pastry for a while, especially the role of the eggs (I'm hoping to be able to make a similar baked good without eggs some day). I've read my way through a lot of articles and some of them claim that the eggs work as a leavening agent. That doesn't make much sense to me though - I can see how beaten eggs or whipped egg whites can help with leavening because the air bubbles will expand in the oven, but the eggs in choux pastry are not beaten.
I guess my question would be: what causes choux pastry to puff up like it should and what is the role of the eggs (stabilizer? emulsifier?) if it's not leavening (I'm open to being wrong about this :D ). Also, if anyone has insights into the other ingredients and processes, please share! As far as I understand, cooking the flour with butter and water causes the starches in the flour to gelatinise and stops the gluten from developing? Does anyone know, how exactly this contributes to the puffing up/texture of the choux pastry?
Looking forward to your comments! :)
"The technique for preparing cream puff pastry [= choux] may seem tediously elaborate, but it's a brilliant invention. It produces an especially rich and most paste that the cook can shape and cook into a hollow, crisp vessel for other ingredients. Cooking the flour with water and fat tenderizes the gluten proteins, preventing them from developing elasticity, and it swells and gelates the start to turn what would normally be a batter into a dough. The subsequent addition of raw eggs contributes to the riches of the yolks and the cohesive, structure-building proteins of the whites, and thins the dough into a near-batter so that air pockets in the interior will be able to move and coalesce during cooking. During the baking, the fat helps crisp and flavor the outer surface. And both eggs and fat contribute to a structure that resists moisture and stays crisp while holding the cream filling." OFAC 2004
Less satisfying on that topic than he is on most others. Suas gives only history, no chemistry.
Tom
Thanks so much for this! At this point, every bit of information helps and this is actually one of the most detailed description I have seen. :)
I have made choux and I have baked GF using xanthan gum and psyllium. Both are stringy and provide structure when baked. I wonder if they would provide structure is substituted in a choux type pastry? It may be an interesting experiment sometime.