Kneading is a process in the making of bread or pasta dough, used to mix the ingredients and add strength to the final product. Its importance lies in the mixing of flour with water. When these two ingredients are combined and kneaded, the gliadin and glutenin proteins in the flour expand and form strands of gluten, which gives bread its texture. (To aid gluten production, many recipes use bread flour, which is higher in protein than all-purpose flour.) The kneading process warms and stretches these gluten strands, eventually creating a springy and elastic dough. If bread dough is not kneaded enough, it will not be able to hold the tiny pockets of gas (CO₂) created by the leavening agent (such as yeast or baking powder), and will collapse, leaving a heavy and dense loaf.