The amount of time in which the dough rests in order to accumulate carbon dioxide in the gluten strands and attain more volume. Overproofing occurs when a fermenting dough has rested too long. Its bubbles have grown so large that they have popped and tunneled, and dough baked at this point would result in a bread with poor structure. Length of rest periods, including proofing, can be determined by time at specific temperatures or by specific characteristics. A bread that is properly proofed will balance gas production with the ability of the bread's gluten structure to contain it, and will exhibit good oven spring when baked.