Bread Tips - Air Holes or Tunnels Inside

Here are some helpful solutions for the common causes:

Air bubbles trapped inside the dough cause holes in the baked bread

Air bubbles which form from the expanding carbon dioxide during the first rise must be eliminated or made smaller. Punching down the dough, then turning it out onto a work surface and kneading it briefly will remove large bubbles. When shaping the dough, pull the dough firmly into shape, or roll out air bubbles with a rolling pin. Pop any air bubbles that show on top of the loaf with a wooden pick.

Bread rose in an area that was too warm

Allow the bread to rise in a draft-free 80°F to 90°F area away from a heat source. If the area is too warm, bread will rise too fast and begin cooking before the yeast has finished acting. Then, when placed to bake in the oven, the "over spring" is exaggerated and large air pockets form inside the dough.

Excess yeast causes large holes

Follow recipe directions. Excess yeast causes extra air bubbles to form, creating holes in the baked bread.

These types of bread are supposed to have uneven holes

You prepared the recipe correctly. The interaction of the various ingredients and the preparation method used for French bread and sourdough bread are intended to create a bread which has a coarse texture and uneven holes.

Source: Tips from Quaker Oats