Pastry Flour has a protein level of 9-10% as opposed to 12-13% found in bread flour. There are four primary types of wheat flours used in baking and they vary in the amount of protein they contain. When moisture is added to the flour, a protein called gluten is developed and depending on the finished product, different amounts of this protein are desired. Since protein gives structure and strength to baked goods, most pastries require a limited amount. Lower levels of protein are found in a softer flour such as pastry flour; whereas the structure of bread demands a higher level.