Irregular air pockets within bread are primarily caused by uneven distribution and excessive expansion of carbon dioxide gas produced during fermentation. This gas, a byproduct of yeast metabolizing sugars, becomes trapped within the gluten network of the dough. Over-proofing, high temperatures, or variations in dough consistency can exacerbate the formation of these sizable voids. A properly proofed and evenly mixed dough, baked at the correct temperature, will yield a more uniform crumb structure.
Understanding the factors that influence gas production and retention is crucial for producing bread with a desirable texture. Bakers manipulate these factors to achieve specific crumb characteristics, from the open, airy structure of ciabatta to the dense, close texture of a sandwich loaf. Historically, bakers relied on experience and intuition to control these variables. Modern baking, however, benefits from scientific understanding, allowing for greater precision and consistency.