Which laminated dough relies on steam for leavening?

• A. Puff pastry
• B. Croissant
• C. Danish
• D. Brioche

Answer: (A)

Steam-based leavening is what gives puff pastry its lift. This dough is made with many ultra-thin layers of dough and butter and contains no yeast or other leavening agents. In the oven, the moisture in the dough and in the butter turns to steam. The steam is trapped between the flaky layers and expands, pushing the layers apart and creating the tall, airy pockets that define puff pastry.

Other laminated pastries like croissant, Danish, and brioche use yeast to rise; steam helps with oven spring, but the primary lift comes from the gas produced by the yeast and the dough’s structure.