What is the primary function of baking powder in pastry dough?

The primary function of baking powder in pastry dough is to provide leavening. Baking powder is a chemical leavening agent that releases carbon dioxide gas when it comes into contact with moisture and heat. This gas gets trapped in the dough, causing it to rise and become light and airy. This process is essential in creating the desired texture in pastries, helping them achieve a fluffy and tender quality.

While baking powder does not contribute to sweetness, flavor, or color directly, its leavening action is vital for the overall structure and mouthfeel of the finished product. The effectiveness of baking powder is crucial in ensuring that baked goods rise adequately during baking, which is why it is a key ingredient in many pastry recipes.