Liquid

Water is necessary to develop some gluten in the flour and to give structure and flakiness to the dough. If too much water is used, the crust will become tough because of too much gluten development. If not enough water is used, the crust will fall apart.

Milk makes a rich dough that browns quickly. However, the crust is less crisp, and the production cost is higher.

Whether water or milk is used, it must be added cold (40°F/4°C or colder) to maintain proper dough temperature.