What is the functions of liquid in pastry?

Liquid in pastry serves several key functions: it hydrates the flour, allowing gluten formation for structure and elasticity; it helps dissolve other ingredients like sugar and salt; and it contributes to the overall texture and moisture of the pastry. Additionally, liquid aids in the activation of leavening agents, promoting rise and creating a flaky or tender crumb. The type and amount of liquid used can significantly influence the final product's characteristics.