What causes shortcrust pastry dough to shrink while baking?

Question

Discover the factors that lead to shortcrust dough shrinkage and how to prevent it.

Answer 1

Shortcrust pastry shrinks during baking primarily due to gluten development and fat melting, both of which cause the dough to contract.

Detailed Explanation:

Shrinkage in shortcrust pastry is a common problem, and understanding the underlying causes can help prevent it. Here's a breakdown:

1. Gluten Development: Gluten is formed when flour is mixed with water. Overmixing the dough encourages gluten development, creating a network of elastic proteins. During baking, this gluten network tightens and contracts, pulling the pastry inwards and causing it to shrink.

2. Fat Melting: Shortcrust pastry relies on solid fat (butter or shortening) to create its characteristic flaky texture. As the fat melts in the oven, it releases moisture and leaves air pockets within the dough. If the gluten structure is too strong, it will contract as the fat melts, leading to shrinkage.

3. Water Evaporation: The water content in the dough turns to steam during baking. If the dough is not properly relaxed or if the gluten is too developed, the steam can cause the pastry to puff up unevenly and then shrink as it cools.

4. Incorrect Handling: Stretching the dough when placing it in the pan can also contribute to shrinkage. The dough will naturally want to return to its original size during baking.

Pro Tip:

Always chill your shortcrust pastry dough for at least 30 minutes before baking. This allows the gluten to relax and the fat to solidify, minimizing shrinkage during baking. Also, blind bake your pastry with pie weights to prevent the base from puffing up.