This part of the web site will focus on pastry used to make pie shells or pie products. At higher temperatures gluten absorbs water and develops more readily. This greater development of gluten could offset the tenderizing effect of the fat. At higher temperatures the plasticity of fats is increased and they become softer. Pure fats have more shortening power than those that contain water such as butter or margarine.
Fats also contribute to the flakiness of pastry by separating the dough into layers.
Softer fats spread more easily and contact more flour particles than firmer fats. Oils tend to coat each particle of flour, which causes a lack of contact of water with the flour and little gluten development. The smaller the proportion of fat, the greater the development of gluten when water is added. Enough fat should be used so that it is able to coat the flour to come extent and product a tender crust that is neither tough nor greasy. A minimum amount of water should be used.