Flour is the foundation of most baked goods, and choosing the right type dramatically affects texture. All-purpose flour, with a medium protein content of 10–12%, is made from a blend of hard and soft wheats and works well for cookies, cakes, muffins, and many breads. Bread flour has a higher protein content of 12–14%, derived from hard wheat, which develops more gluten and produces chewier, more structured loaves that absorb more water. At the opposite end, cake flour contains just 7–9% protein from soft wheat and is often bleached; this fine-milled flour produces tender, delicate cakes with a soft crumb, partly because the bleaching weakens gluten formation and helps the flour absorb more sugar and fat. Pastry flour sits between cake and all-purpose flours with 8–10% protein, ideal for flaky pie crusts, biscuits, and scones, and can be approximated by mixing equal parts cake and all-purpose flour. Whole wheat flour includes the entire wheat kernel—the bran, germ, and endosperm—giving it higher fiber and 13–14% protein, though its bran cuts through gluten strands and often requires blending with white flour for better texture. Self-rising flour is a convenience product: all-purpose flour pre-mixed with about 1.5 teaspoons of baking powder and ¼ teaspoon of salt per cup.
Gluten itself is a network of two proteins—glutenin and gliadin—that forms when flour meets water. Glutenin provides elasticity, the ability to spring back, while gliadin provides extensibility, the ability to stretch without snapping. Together, they create the structural web that traps gases during fermentation and gives bread its characteristic chew. Kneading aligns these proteins through mechanical action, organizing them into a strong network. Under-kneading leaves the structure weak and unable to hold gas, while over-kneading tears the network and makes dough tough. The windowpane test is a simple way to check gluten development: stretch a small piece of dough thin enough to see light through it without tearing; if it forms a translucent membrane, gluten is ready.
Before kneading begins, bakers can use a technique called autolyse: mixing just flour and water and letting the dough rest for 20 to 60 minutes before adding salt and yeast. This rest allows the flour to fully hydrate and gluten to begin forming passively, which leads to better dough extensibility, easier kneading, and improved final texture in bread.